(1) Well, yes, Allan, I definitely agree -- you can read for tone. In fact, I think it's a good skill for dealing with any piece of literature. And I surely agree it is possible to determine the tone of sentences without tone indicators.
"Alistair, you are a sad pathetic, excuse of a man, always afraid to face your life's responsibilities!"
"Alistair, you need to stop being so hard on yourself, and realize it's OK to accept your fears."
I don't think I need a Diplomatic tone marker to figure out the diplomatic sentence from the angry one -- do I?
But, as you just said, you READ to figure out which sentence was friendly, and then picked the friendly sentence, because it was friendly. Or the angry sentence, to decide if it was angry. What that of course makes players do is have to read dialogue and think about their choices, even if it is only to figure out which sentence will be perceived as angry and which one will be perceived as friendly.
The point is, once you signal to the player "this is the friendly response" then I agree they have to do almost no thinking at all. (Well, at least if their approach to giving dialogue responses is similar to yours.) In fact, if you do as some people want and make sure that the friendly response is always in the same position on the wheel, they don't even have to think that much. All they have to think is "pick upper right". "Pick upper right".
Which means, they have to do hardly any thinking at all. And as you may have noted, I really prefer to do more thinking in games, not less.
I'm not sure it required much "thinking" about my choice. At least not in any meaningfully interesting way. I think I could argue that it prevents a barrier since if I am trying to decipher which response is appropriate for how to respond, I'm not sure if that's the type of thinking that is necessarily considered positive. For instance, Mass Effect 3's Rannoch scene provided two choices that I spent a lot of time thinking about, but I was thinking about which choice to make, as opposed to thinking "what exactly do each of these choices represent?" Perhaps ironically, I think that that's the type of stuff that I fight with, akin to how you fight with the idea of "I didn't want my player to say specifically that."
That's not that I don't like thinking in my games at all. During conversations, especially when the stakes are high, I'd qualify my engagement as pretty high and I'm constantly thinking and evaluating what the best course of action would be. Sometimes tone is a game in and of itself, as some characters can respond to lines in a particular way.
As for the tone marker, to be honest it'd still come in handy even with full lines. I've picked lines that I read sarcastically, but the dialogue plays out as though it was done differently.
(2) I may disagree with Sylvius on this, but no I was not a fan of the keyword system of the Ultimas. In fact, I really only felt a satisfying dialogue system when I first started playing certain CRPG games in the 90s, including many made by Bioware.
I was a big fan of the dialogue system in BG2 (made by Bioware), NWN1 (made by Bioware), KOTOR1 (made by Bioware), and DA:O (made by Bioware), though I also have to give props to the system in Planescape Torment and Fallout, though those were not made by Bioware. (Plus NWN2, and KOTOR2, of course, but likewise.)
Now, please note, I'm not saying Bioware shouldn't innovate, nor that all innovations in the dialogue area have not been good, but I do have to confess I got the taste for dialogue selection I did in many cases from Bioware games, and I also have to confess I never got the idea why, exactly, it was necessary to reinvent the wheel. So to speak. Now I recognize all the games I'm talking about had an unvoiced protagonist. That said, it's not clear that a voiced protagonist had to wind us up where we are now, although we are here.
I saw it as the continued extension of the push to a more cinematic flair. I remember thinking "It'd be cool if all the lines were voiced" in BG2. Then I remember thinking "it'd be cool if the player was also voiced" with KOTOR. There are issues that I know I have once the protagonist is voiced, often relating to subvocalization.
One of the reasons I don't play with subtitles on is because I will read the subtitles before the line is delivered. Mentally, I am now waiting for the line to delivered, when I've already heard and experienced the line as I read it. This actually is a negative for me, because now I'm waiting... but perhaps cannot skip because the actions of the PC may be relevant to what is going on. So I turn the subtitles off (I actually have gotten better at reading along with subtitles when they're on, but then I am reading the subtitles, not the activity as it's going on). Presenting me with a full line of dialogue prior to speaking it places a stronger cognitive strain on me as I watch the dialogue play out while already knowing what is going to be said.
I mentioned Deus Ex Human Revolution, but not for the reasons that you like it. When I say I like what DEHR does, I'm not referring to the inclusion of the full lines of dialogue. It could not exist and I'd be okay with it. So I think it's disingenuous to point out that because I like DEHR (and cite it as an example), to twist it into evidently being support for a system that would display both. Almost frustratingly so, though perhaps also because you're not the first person to do so. (Aside: I mentioned the game - I don't think it comes across as positively as you may intend for it to by explaining to me a system and feature I'm already aware of.... If it worked for people then I am happy for them. It's not a huge deal for myself)
It also lacks context (I recommend playing the game, both because it's quality and because it might help), because while Deus Ex's conversations (the "conversation challenges in particular") are very interesting, but they're also not nearly as reactive as we try to make ours.
So while we may have 3 or 4 line entries that all belong to the same speaker in our dialogue, by breaking the lines up we provide various entry/exit points for those lines. Imagine the conversation editor has something like this (all lines spoken by the player character... the bulleted lines represent lines that are determined based upon the player character's race.
"You dare to question my background...."
- Growing up in Orzammar was not without challenges
- You try growing up in a cutoff alienage where people think you're a freak
- Imagine living in a place where those that claim to protect you can cut you off from your very nature
- I'm a Cousland! You best pay me the respect my family deserves!
There's no situation like this in Deus Ex. The conversation lines that are given to you at any particular point of the conversation are always the same, and don't really react to choices the player makes barring some situations where an extra option plays out because Jensen has some extra information/context (which is still a nice thing in the game).
In order to replicate the "full dialogue line" in Deus Ex's style, we'd either have to have the system read ahead of the current dialogue lines (this isn't without risk*) and pieces together the lines into a single entry for the player to now see. Since our conversations can branch during these, the system is more complicated than simply taking the line as it is, or taking a fixed/predictable subset of the line as Human Revolution does. Is it worth the effort? I'm sure you think so. But keep in mind that people that worked on the old BG games that did what you prefer are still key stakeholders in our current games.
Mark Darrah was the programming lead for Baldur's Gate 2, Mike Laidlaw was a writer for Jade Empire, and Gaider has been around since BG2 as well, while Casey Hudson was the guy behind KOTOR that then made Mass Effect. I think if you piece together BioWare's history of games, the emphasis has always been on the game's narrative and that the presentation of that narrative has gotten increasingly cinematic as technology allowed for it. So it's not like these decisions aren't made without any acknowledgements of how the old way of doing it once was.
* The DAI conversation system does do some amount of preloading for performance reasons, but only for NPC lines since those lines are predictable, and only if there are no conditions on the line. But it still has risks because, for example, the first implementation of this had the read ahead inadvertently treat the lines as being reach in game... so conversation lines were firing the scripts attached to them before they should. This is also why the system doesn't preload past conditioned lines, because it's possible the condition may be influenced by the preceding line. Even then, DAI's system is a preload that only refers to caching lines for performance reason. The game doesn't actually "know" what lines are about to be said in any meaningful way... only that "DataString ##### is now at memory address 0x########"