S'mon, as to your comments about "Primal-esque" canon lawyering... as I said in an earlier post, I'm not against changes to canon *if* they benefit the campaign and also make sense (do not violate internal consistency and/or are believable). For example, I'd probably walk out if the DM started with "Alright, guys, you're travelling from Silverymoon to the village of Hommlet to investigate some rumours about a cult of Vecna...". However, if the DM chose to have the bland and generic 8th level local lord replaced with a more interesting NPC, I'd have no objections to that; I do that myself in every campaign (i.e. I read the relevant supplements I own and then pick what I like and change the rest to better fit the campaign).
Of course, if the DM only owns the Grey Boxed Set, I don't expect him to suddenly buy every book that has some lore about Town X. Absence of lore is not what usually troubles me (I *do* have a problem with DMs who don't detail the area at all, and generally don't do NPC descriptions)... rather, what really bugs me is glaring inconsistencies with the canon that are not explained in or out of the story (e.g. a Cormyrean town that's "alway's been a Zhentarim town"). And, of course, that the lore DM chooses to replace the canon with does not feel "Realms-y", e.g. local lords with RW names or homebrewed deities.
So, when you're running a game to
FR "veterans", it's good to be familiar with the setting in general, and not just the local area, but I'm not advocating that you should read and own every book to be able to run a
FR campaign. If you want to run a
FR campaign set in 1357, I'd be totally cool with that.