Grog said:But this isn't a solution, for a couple of reasons. First, as has been pointed out, at high levels, mooks start throwing save-or-die effects. Like I said, when encountered by a 17th level party, a 13th level cleric is supposed to be a mook who they can take down with ease. But that mook can throw a save-or-die that has a 1 in 3 chance (or thereabouts) of instantly killing a PC. So, unless the PCs are going to start casting divination spells before they open every single door in the dungeon (which would slow the game down to a crawl), divination spells aren't a reliable way to anticipate when they'll be faced with save-or-die effects.
And second, at high levels, many enemies the PCs will face will have access to exactly the same divination spells that they have. So if the PCs use divination magic to find out that the evil wizard they're going up against likes to use save-or-die spells, there's no reason that the wizard can't use divination magic to find out that the PCs will be arriving at his lair with Death Wards up, and either use Disjunction or whatever to get rid of them, or simply go somewhere else and wait for them to wear off, then return and start killing PCs once they're no longer protected. Again, it's not a reliable defense.
In think this post illustrates why the game changes, and should change, at higher levels. The encounter-fighter-encounter paradigm of low and mid levels is much harder to maintain, both mechanically and thematically. Older editions realized this and as soon as they starting capping HD at the same time wizards got high level spells and everyone started becoming leaders and landowners.
That shift in focus might actually promote some of the core assumptions of 4E. A transferrence from per-day to per-encounter resources makes sense when a party might have one encounter per month, between negotiating with rival barnonies, researching powerful items and running their own country.
Something to think on...