Lore doesn't create a shared experience. Playing the game does that. Lore just helps(many peopl greatly) color the shared experience that the players are creating.
When [MENTION=3400]billd91[/MENTION] talks about "shared experience" he is meaning shared across groups, not within groups.It absolutely helps with the shared experience, just as work you do helps with it.
If lore is essentially ignorable - eg the MM says blue dragons like desert but every blud dragon actually encountered in play is an exception like the one in RttoEE - then how is that shared experience being created? Your blue dragon was the RttToEE one; my blue dragon was another exception, living in a forest; etc - where is the shared experience built on common lore?
What limb? If it's OK for Monte Cook to ignore the MM and put a blue dragon wherever he wants, what is going to happen to a GM - rookie or otherwise - who does the same thing? What is the (metaphorical) risk of falling of this (metaphorical) limb?Some aren't that creative. Others don't have the experience yet and don't want to step out onto that limb.
Throws them off how? And how worse than the examples I've given, all of which place monsters in complete disregard of their lore?The MM writers do occasionally make those changes, and it throws off some DMs and players who rely lore and who know about the prior lore.
D&D is a game, to be played. How does reading something different throw you off, but actually playing a session in which a blue dragon is not in the desert doesn't throw you off? What is the mental process here? I mean, does it become easier to play the dragon-out-of-desert when you know that, typically, it would be in a desert, than if someone had rewritten the MM to delete that particular bit of dragon lore?