Why does my point about Alexius beating your forces not hold up? Is he not allowed to use his Time magic to defeat you? Is that cheating in your opinion?! Would you call the referee in?! You knew he had control over time magic, knew you had no way of stopping it and challenged him anyway. You can't just stamp your feet and say 'If it wasn't for that cheating time magic, we'd have won!' He used his best weapons against you, and you lost. As you were always going to, when you had no defence against it. Your argument makes no sense at all.
And don't you think its grasping at straws at straws to say the Templars probably couldn't help, because they have failed to control magic before? When they storm the Gallows in DA2, they absolutely whup the mages in that introductory cutscene. They are only thrown back at all because of Hawke and the gang (in the Mages supporting version anyway), and even then at such a dreadful toll in Mage lives, that it drives Orsino out of his wits. They are reknowned for their anti magic capabilities. Maybe they can't help you against this magic, but they are your best bet surely to goodness, and a damn sight better than having nothing! The Templars reputation for magic suppression and success against magic of all kinds is long established. I agree that Bioware haven't been very good at showing that, but that is on their storytelling - if the Templars were really that bad at suppressing magic, that is the view people in Thedas would have of them, and it isn't. The Templars have simply been a victim of Bioware favoring the mages (until this game) and generally casting them in an antagonistic light until now (which has been noticeable, because since DAI was released which shows them in a more positive light, the support for them on forums like this has vastly increased).
You say I've made claims about why they failed. I've told you, but you just don't want to listen. They lost because you were taken out of play by his Time Magic. The magic you claim Dorian is your best asset against. This is despite him admitting that the version he saw did not work. And having compelling reasons to apprehend him, does not give you the means to actually do so, without it being an absurd risk (which is Cullen's point - he wants to take Alexius down, but not if this is the only plan you have. Even though he muses it might work, he still insists (correctly) that it far too long a shot, and you should go for the Templars instead. Plunging in without either them or Ferelden forces (for the simple reason that you don't think they'll give you permission of all things!), is an incredibiy stupid move.
And how is this scouting of enemy numbers to work exactly? The windwill entrance is exposed to open air, seeing as how the mill has fallen apart. It stands alone on a hill with nothing else there. So these agents are going to go up there, sneak in, head into the castle, nose around a bit to determine numbers (given that the castle is large, and if they are found that's the end of that), and then come back? Then an even larger number of them is going to go up this ridge, hoping that nobody will notice that a consistent stream of people have been heading up there and not coming back, in sufficient numbers to tackle a castle's worth of enemies? And you're suprised that this failed?
I don't see what is so hard to grasp here. You are insisting that the plan *could* work, but it *didn't* work, did it? And you were warned repeatedly that it stood a high chance of failing, because of the difficulty in getting your people in there in sufficient numbers, and because you lacked the means to confront Alexius' magic. Instead you keep insisting that if they hadn't used their deadliest weapon (the one that forms the basis for why you are going there!), you might have won. What kind of absurd logic are you working under? This was not a sound plan at all, and you were told this by your military advisor. If you don't trust him on this (and he could not have been more forceful, outright telling you that he wouldn't allow it), then why are you even keeping him around? It was a supremely stupid plan, that saw you outnumbered, unsure of the loyalties of the parties involved, certain that you had no defence against the weapon the enemy were using, and heading into the place in 2 teams, who cannot co-ordinate (i.e if Alexius had attacked immediately upon your arrival, it wouldn't have mattered what your other team was doing - ditto if they were delayed somehow and had to retreat. You wouldn't know about it until it was too late).
The Inqusiition's mandate was to stop the Mage/Templar war. The writ was issued before the Breach, before the venatori were known, before Corypheus was known. The Inquisition then uses that writ to expand its mandate to closing the breach (which is instantly contested by the Chantry, as that is NOT what the writ alows them to do at all). You have obtained no permission or recognition from Ferelden to act in this manner on their lands (which Alistair also points out later, but in light of Haven, he's willing to let that slide). But at this point, you have no such leeway. You have no proof that the venatori were involved in anything, and even if you did, you still wouldn't have the jurisdiction to do anything about it. And AGAIN, in case you didn't hear the first 20 times, you do not have the training or expertise to deal with this problem. You will make it worse by blundering in like this.
And make it worse you indeed do. Because if you ignore this and go after the Templars, the dark future is avoided. Why? Because you don't fall into the obvious trap that you knew was being laid for you. Boldly stepping forth and springing the trap is much less impressive when you do it by actually falling into the trap and having it work! You heading into Redcliffe, undermanned, with a lack of suffficient information and magical protection produced exactly the results you deserved! The Dark Future only happens because you take an unacceptable risk, because the world cannot, absolutely *cannot* afford for anything to happen to you. You are the *only* person in the whole world who can close the rifts. And this is precisely the point I was making a month or so ago in the 'I just don't get it' thread about why the basic premise for Inquisition is so flawed (because if you really were the only one who could close the rifts, they would never let you out of Haven/Skyhold without a full bodyguard of dozens and dozens of soldiers, to escort you to rifts, close them and then march quickly back to base).
Any risk you take personally in this game is magnified exponentially in magnitude, because if something does happen to you, then its game over for the world, as they will be left with no defence against the breach and the rifts. Cullen tries to tell you this over and over and over again, that it is too risky for you of all people to be doing this. And so it proves. Bumbling into Alexius; trap and getting yourself removed from play, is what triggers the Dark Future. Losing you to an obvious trap with unlikely odds of success is too much of a risk, to try to remove this threat. Even in you could be sure that these guys were the ones responsible for the Breach, you still shouldn't tackle them alone like this, in such an appallingly thrown together at the last minute kind of way. Cullen is right when he tells you that even if your instincts say you should get this guy, a wise man lives to fight another day. Alexius has the advantage in every way possible. Refusing to accept that is suicidal and stupid, and because of the necessity of your Mark, endangers countless more lives than just your own. You're gambling with the lives of everyone, on a plan that is unlikely to succeed, and which you don't need to do, because you have another option. The implications for your loss are too great - and that's exactly what happens, because you insist on charging in and just hoping this Time Magic isn't all its cracked up to be...
By sheer providence, you are taken to a time where escape is possible, but that is the luck of the Gods themselves, and is no basis for a plan. For example, if King Cailan at Ostagar had said 'Guys, guys, I've got a great plan. Instead of using the army... I'll charge out there with a pair of knuckledusters and I'll show the whole lot of them some Royal Ferelden Justice! How's that grab you?'Idiocy, right? But if he then ran out there and a freak meteor fell from the sky, wiping out the whole darkspawn horde and leaving him victorious, would that make it a good plan then? Since he eventually succeeded, even if it was because of being the luckiest man who ever lived? That is your Inquisitor in Redcliffe. You have a terrible plan, it goes exactly as it deserved to go (i.e awfully), and then by utter fool's luck, you manage to turn it all around when instead that magic could have sent you thousands of years into the past or future. You could have been seperaed from Dorian, Alexius and his spell could have been gone. Any number of billions of possibilities, yet you luckily get taken somewhere you can reverse it -Which you cannot possibly have predicted would happen.
If that's the kind of plan we're accepting as good ideas, then why not bank on the solo guy/Meteor theory to win all your battles? Its just as likely.
And I'm not saying you're acting against Ferelden. I'm saying removing Tevinters from a Ferelden castle isn't your job, nor is it your jurisdiction. So what if the Venatori are a foreign cult. You are not the police, you do not represent Ferelden and saying that you are 'saving' the mages, assumes they want to be saved. You have talked to what, 4-5 mages? And some of them support the merger. How many more do? You don't speak for them either. If they want to go through with this deal, its their business. If Ferelden want the Tevinters out of their town, that's their business. None of it is *your* business. Because even if you think they are interested in you, that is no legal basis to act.
Put it this way. Assume for one moment that cult or no, the Venatori are simply Tevinter supremacists, who have co-opted the Mages through a variety of coercion and bribes etc. They may even still be using Time magic etc etc. None of this is actually illegal. Let's say you get in there, find out that they are nasty bit of goods, but that they haven't actually done anything wrong (beyond seizing the castle, but again that isn't your business). You had no evidence either way at this point. If they didn't prove to later be allied with Corypheus (who you don't even know about yet), then your actions would simply be an outrageous invasion and interference in matters that did not concern you.
Which is how everyone views it at the completion of this quest, because that is exactly how it seems. You have sabotaged the deal for your own ends, and violated Ferelden land and jurisdiction to do so. Haven sets them straight, but that is information and confirmation that they cannot have known at this time. You of course also don't know any of this until you see the Dark Future, but if you tried to sell that to anyone, it'd be 'Ah yes.. 'Reapers' time again. You are buying into this idea that because you're the guys who get **** done, that everyone else should just bend over and let you get on with it. Well, that's not how things work!
All this insisting on this long shot plan is silly, especially as the plan is *shown* to fail! And yet you insist its a better bet than going after the Templars, because their leader told you No - once. Your country must be very relieved that you aren't one of their diplomats, Heimdall. If you take the first answer in a negotiation and say 'Oh well, we tried... let's go' then you won't get very far! Lucius can't simply say No without explaining himself when enough important people gather to force him. You don't have to take his first answer as his last! And as Cullen points out, Sod what he thinks anyway, after his antics in Val Royeaux. If he won't listen to reason, then others will. The Templars would completely destroy their credibility if when confronted by the nobility, they refused point blank to do their job. They would lose all their support, resources and once word got out, the support of the people as well. Something Barris and Cullen are sensible enough to point out.