Wow I have a lot to respond to. I'm just going to be lazy and do each post day by day.
The Reapers actually don't fire much on the Crucible. You'd think that if they decided to fire on the Crucible, it would be game over for Shepard and pals. The Reapers also just float around the Crucible while Shepard is with the Catalyst and give no shits. So if Shepard chooses the Refuse ending, there is really no reason to believe that the Catalyst has no control over the Crucible/Citadel/Crucidel.
Well, but what exactly the Crucible can do in the end is tied to your EMS and how much damage the Crucible has taken. The Catalyst states that either the device is largely intact (high EMS) or damaged (low EMS), so I always took it as: more EMS, more fleets to distract Reapers from shooting, less EMS, less fleets are there to take the fight to the Reapers. I guess it depends on where they would hit, but well, something is happening in low EMS to make the Crucible more damaged. And I get your reasoning for a Reaper firing at the Crucible, but then we don't know exactly how the energy is actually created, if it's happening in a tiny core/going through tubes well hidden/shielded or not. If that were the case there'd be a chance I think.
I know about Refuse, and it's what makes me constantly wonder, but then actually you could have a game over in the original ending in which it was stated that the Crucible was destroyed by the Reapers. That's what ultimately made me think about it as a possibility.
I like it when the player can also leave events in the story or how things work up to themselves, but there's a fine line between ambiguity and simply not making sense that the Synthesis ending does at least 20 backflips over. You can speculate that the Control ending sends a signal to each Reaper that makes it obey Shepard's consciousness and you can speculate that the Destroy ending is an EMP (although as I mentioned before there are even a few issues with this idea), but how can you speculate anything about the Synthesis ending and have it make sense?
I don't know, as I'm not one of the people that likes to choose Synthesis, haha. I chose it the very first time (it was late into the night, and peace and the synthetics getting to live sounded so nice, so I was gladly ready to sacrifice myself), but it was totally strange. I reloaded immediately to pick Destroy.
But like I said, maybe it is something that can't really be explained, it's a question of what Shepard is or represents etc etc. Don't know.
It's purpose isn't to offer choices, but solutions is what I'm getting at. The Catalyst leads the Reapers and was programmed to find solutions to a problem. It has been acting over hundreds of thousands of years on what it thinks is the only solution. But suddenly when Shepard shows up, it decides to change everything and offer 2 non-solutions and one how-does-this-even-work solution(???). And once again, the Catalyst came up with these solutions and it claims it has control over the Reapers. There is no possible way it shouldn't be able to act.
Yet it tells us that it can't. I'm not sure what to say here anymore to be honest
I guess we can just leave it at that. To me, since it states it cannot do act and that the Crucible has changed it and created new possibilities when Shepard asks why it's helping him/her, it's enough for me to see that it just can't really do anything. Why else would it say that?
The Crucible is designed as a power source. If the Crucible was to start off as a weapon and then later be adapted into a power source for the Citadel, that makes even less sense to me. So you're part of the civilization building the Crucible. It's supposed to be a weapon, but later on you adapt it to work with the Citadel. How did that civilization know the Citadel could be used that way and how did they even have access to the Citadel to adapt it into a power source. Remember that the Reapers invaded via the Citadel until the Protheans sabotaged it. The current cycle is the only cycle to not have had the Reapers invade via the Citadel. So how did that civilization get the Crucible to work with the Citadel when the Citadel was already under Reaper control? And if the true functions of the Citadel was hidden from so many other civilizations, how did this one manage to discover them?
Once again though, the Reapers really never lay a finger on the Crucible. Even in the low EMS cinematic, the Reapers focus fire on the ships rather than the Crucible. Considering that the actual size of the Crucible is rather small when it comes out of its shell, this is really odd as a single Reaper laser could probably slice right through it. it actually looks like the Citadel itself is under more of an attack which is odd because you'd think a Reaper would not want to shoot where their main AI is. Even if the Reapers were attacking the Crucible, all the Catalyst needs to do is redirect their fire as he has control over the Reapers. He can give Shepard all the time he wants, there really is no reason he's in such a hurry.
Well maybe it is simply not the right word choice then, but it is capable to deal with the Reapers, and was referred to as a weapon in early ME3 as well.
But why does it make less sense? The Crucible was build to disperse energy to get rid of the Reapers (I assume this was the original intent), but maybe civilizations realized it was not enough to target them completely or something along those lines. Maybe they figured if they used the Citadel in its open star-shaped form, it could disperse the energy further. Of course we don't know what exactly they did, how they studied it, or how they had this idea, but why not? We were told that they used the Reapers' own technology on them, incorporated the Citadel to make use of it, being the central relay hub. In these instances they don't need any knowledge of the AI. They just use Reaper inventions to get back at them.
And maybe they did something similar like the Protheans. Top scientists working secretly in some hidden bunker after the Reaper attack to develop a countermeasure until they also were wiped out by the Reapers. Before that happened they hid the plans, so the next cycle would find them. I can see something like this, I guess.
Honestly, I don't really care how it all started, it's details I don't need for the ending of the game, but if you want you can make it up somehow I think. I still stand by my opinion that the writers deliberately chose to not include these details because of the "there's no time" element. I know that the conversation with Anderson was cut short as well. It was supposed to be longer, but they (I think it was Casey's decision, but no guarantees) wanted it to be over much quicker.
Also, about how they knew the Citadel would work? They wouldn't I think. They didn't deploy the device, otherwise there would've already been changes to the Reapers. So they only worked on it in theory, each cycle adding new stuff to make it more efficient. In theory
Makes this whole damn thing even more miraculous, but that's how it is I guess.
And I don't really think there's anything wrong with the inclusion of a chamber of choices, but its design is fishy as hell. The idea that the Catalyst and Reapers were huddled around and were like "You know what the Citadel tower needs? A thing to shoot to kill us all, something people can grab to control us, and a nice big damn laser beam so people can jump into it and, like, become ROBOT PEOPLE.". Or if you believe that the chamber of choices was designed by another race, simply take the imaginative quote I pulled out of my backside and apply it to them. I don't believe that chamber of choices blasted off from the Crucible though. Otherwise, why would the platforms that lead to the choices rise from the Citadel and how does one accurately launch a giant...thing into the top of the Citadel tower without screwing something up?
Yeah, it makes not much sense to have the tubes and the handles for Destroy and Control built upon the Citadel. It makes no sense at all, considering that is not what the Catalyst wants. So I really like the idea it's coming from the Crucible. There's some sort of tires around if you look at the design of the decision chambers, which could indicate that they were not attached to the Citadel, but came from the Crucible.
Btw, I also don't think that the Synthesis beam idea ever came from the Catalyst, but that it is rather a byproduct from the Crucible's energy. The Catalyst doesn't seem to know that Synthesis is possible with the Crucible, since it also wanted the plans destroyed earlier.
That's what I'm often saying. Each player will be prepared for the big end question, what to choose. What is the best, or rather most logical choice for each Shepard?
Personally I try to have a certain mindset for Shepards that are or aren't open to some things. If I play a Shepard that doesn't care about synthetics, even chose to destroy the geth on Rannoch, why would I even consider anything but Destroy? If I favour Synthetics and want them to have a chance I picked Destroy in the past too (this was a Shepard that wanted to give Synthetics a chance, but couldn't broker peace on Rannoch and chose the quarians), but a different Shepard could pick Synthesis or even Control. While I as a player don't like anything but Destroy, maybe I'll pick something else at some point for my Shepards.