This whole 'out of the fiction' vs. 'out of character' dilemma, or whatever differentiations gamers have made about this bit of terminology, is the result of me not being aware of the difference. As I'm not terribly interested in whatever difference lies between 'out of the fiction' and 'out of character' at the moment, feel free to substitute one for the other if it better fits your experience. Thus, my original comment can be rephrased as 'Gamers who talk about dissociative mechanics seem to be very concerned about overly-involved mechanics taking them out of character.'
Anyhow, now that you've described 'dissociative mechanics' to me, it seems more and more like a very selective criticism to make, given all of the D&Disms that many gamers have found to be un-immersive over the years. I mean, what's the rule-to-game-world translation of the 'monsters lose their infravision, should they ever ally with the PCs' rule? What's the rule-to-game-world translation of the 'a glowing magic sword can't be turned off, except that it doesn't turn on until a PC identifies it, because having the PCs find a glowing sword is too much of a giveaway!' rule? What's the rule-to-game-world translation of the 'Wizards shall not heal!' tradition?
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