SO...are you saying the DM should spend a few hours of the game session each week dealing with a players Half-Dragon Rainbow Adept's new spell list, or just alot a few hours away from his career or kids?
Seriously, despite the fact that my players all decided on the Core Three only rule, I don't think a DM who limits the number of optional rules at his table is in any way a bad DM. As a matter of fact, I would have to say that any DM with the time read, analyze, and modify any of more than 1000 published feats, spells, and PrCs is simply a DM without a job and family!
I've played with a lot a great DMs who didn't need to roll out the red carpet for every bizarre .pdf full of nonsense someone happened to bring in the door, and yet still, unbelievably , managed to run a fantastic, fun, and engaging game.
Heh. I may have given the wrong impression here. I don't mean the GM has to be aware of everything ever published for d20. That, I agree, is an absurd stance. And nowhere did I say that the GM has to *allow* anything and everything. Quite the opposite, in fact, as should be blatantly obvious if my post is reread. Some stuff should never be allowed in a campaign for balance or flavour reasons. I just believe a (experienced) GM should not close options off for players simply because he can't be bothered to examine what the player wants to do.
What I mean can perhaps best be illustrated by example. If a player wants (as one of mine did) to play a Duskblade from the PHB2, I spend the 10-20 minutes required to examine the class, and allow/deny/modify it as needed. Later on, let's say the player wants the Arcane Strike feat from Complete Warrior for his Duskblade. I then examine that feat, consider how it would affect his character, and allow/deny/modify it as needed.
Character generation is by definition a time-intensive process. It also doesn't come up that often (and certainly nowhere near 'each week' as your melodramatic example implies). Spells and feats are a *lot* less time-intesive to examine, and come up a lot more often. You don't have to be aware of everything in every single d20 product ever published. You just have to be willing to spend the time to look at something a player wants, and work with that player so he's happy. I don't see how that's such a big issue.
And I don't deny that some GMs can create perfectly entertaining campaigns while arbitrarily limiting their players' choices. I would argue, however, that such campaigns are rare; GMs that go into a game with a mindset of limiting players' choices due to being unwilling to spend the extra time involved, usually extend that philosophy into all aspects of the campaign, to the ruin of the game, in my experience. And the rare good campaigns would have been even
better if the players had been allowed more freedom within it. It's such an unfortunate omission as well, since it has the potential to bring the player so much more enjoyment for so little effort.
--Oh, and just for the record: I have a full-time job, and I'm happily married with a teenage daughter. And I am currently running two weekly campaigns. Using the guidelines I've listed above. I'm not saying this to preen with pride, or anything like that; I don't feel like it's been any great burden to GM this way.
Edit: Clarifications. : )