Speech checks aren't used to see if an NPC can successfully lie to you. Also, we've already designed in the era of invisible stat checks. They lead to players believing that their statistics actually have no effect on conversations. They literally don't know what they're missing.
In Darklands' Expert mode, greyed out/unavailable options were completely removed. You'd enter an interaction screen and see one or two options, not realizing that there are a ton of other things you could do if you only knew this saint/had that potion/bumped that skill. It's great for people who've already played the game 10 times, but for other people, it removed the impression that those saints/potions/skills had utility outside of their normal systemic use.
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I'd like to look into options to disable messages of that sort (skill checks, attribute checks, reputation gain and loss), but in practice I think many people will either a) not use them or b) use them only for immersion purposes and metagame around their absence.
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Like I wrote, I don't have any objections to optionally turning things off, but I have no illusions about how most people actually play these games vs. how they say they want to play them. I've been watching them do it and dealing with the aftermath for ~13 years.