billd91
Not your screen monkey (he/him)
Exactly how much can fit in a bag of holding? How many people can fit on the carpet of flying or the folding boat? What does a belt of giant strength do? Obviously a +1 flametongue sword has something to do with fire, but what exactly are the mechanics (especially pre-3.x when the effects of that kind of thing were largely standardized)? And I grabbed the DM's copy of the DMG when I was playing 2e (because I was a broke college student and didn't have my own), or in 3.x brought my own copy. Of what was supposed to be a DM's book, but I had a copy anyway even though I never ran a game in person (in other annoying multi-book stuff, stats for summoned animals and common riding animals -- yup, in the monster manual, which players are even less likely to have than the DMG).
It's less a question of keeping the information away from the players as making it clear that magic items and their approval and distribution is part of the DM's sphere and responsibility. If you want the PCs to have regular access to the text describing their magic items, stick it on a note card. Works great.
Magic items are essential unless WotC wants to radically depart from prior norms for D&D or wants broken math. And only the barest handful of them are campaign-specific.
Actually, they're all campaign-specific in a way. There are very few campaigns that will actively incorporate all of the magic items in the core rules. There will, most likely, be a few handfuls of items. Including all of that, in addition to all the spells that PCs have more regular access to, strikes me as unnecessary bloat for the player book.