I can't speak for anyone else, but, I certainly don't mean to badger.
The math is pretty straightforward. A creature, by and large, can dish out CRx10 damage in 3e. Give or take anyway. Very, very few characters have Levelx10 hp's, unless you are giving max hit points per level. Thus, an equivalent CR creature can (not highly likely, but possible) kill a PC in one round. Never mind the 4 rounds that a fight is supposed to last.
CRx10? That seems high to me. Creatures like giants might have damage on that order, but they tend to be more vulnerable to magic.
I do typically find that getting a mage into the thick of the fight is usually bad news, as the typical CR=APL creature IS an immediate threat to an undefended mage, but a fighter type can usually hold out.
Nonetheless, my experience with my higher level groups is that except for EL >> APL fights, the fight is typically short.
So, what are you doing differently than me? Are you using large numbers of very small CR's to make up EL's, instead of smaller numbers of larger creatures?
That varies. I find fights last longer with more creatures, regardless of CR, and makes the situation more complicated for the players. Perhaps my players focussed too much on damaging one target and weren't so good at dealing with spread out targets. (In the 3.0 game, the monk/rogue pair tended to flank and take out single targets in short order, and the sorcerer didn't come into his own in dealing with multi-creature situations until he picked up Horrid Wilting, which allowed him to deal with targets intermixed with the party, bypass energy resistances, and bypass evasion.)
I avoid fudging dice, unless I goofed up. I can and do tune encounters by ear. If a random creature chart says 2-8 creatures, I pick instead of rolling.
Do you have house rules that mitigate death or massive damage spikes like crits?
I use a critical injury rule which might actually be more annoying than the standard rules, but it usually only comes into play in ECL > APL encounters.
Are your PC's using very high stats? Perhaps they are much wealthier than baseline?
I'm basing this discussion mostly on two long term campaigns, my 3.0 campaign that ran from 1st-22nd, and my 3.5 campaign that ran from 4th-16th. They were both mixed campaigns with city, wilderness, and dungeon elements, as is my norm.
I allowed good stats (random, but with averages towards the top end of the point scale).
For the 3.0 campaign, wealth was probably above average. In both games, I didn't use magic wal-marts. All item availability other than PC construction is randomized.
The 3.5 campaign was probably more in line with the standard wealth, but it used action points. The fighter did a very good sword I was constantly having to circumvent. It was easier for me to push PCs to the limit in that one, due to the action points. But then, I think encounter design got nastier in 3.5. The 3.5 campaign went a LONG time without casualties. But then I ran the PCs through the Age of Worms adventure Spire of Long Shadows:
[sblock]There was a trio of kyuss knights, which the PCs had never faced before. The group threw up movement control like Spike Stones assuming they were melee combatants. The kyuss knights threw negative energy bolts. Every PC but one got killed in one round. I generously allowed the last PC standing to teleport the bodies out of there.[/sblock]
In other words, how are your players surviving while mine die like flies?
And, before I get knocked again for bashing 3e, I've been asking this since I started running the World's Largest Dungeon about three years ago. Long before 4e was announced. This has been a problem for me and my games for a very long time. You apparently have solved this problem. Since I'm going to be running another 3.5 game shortly, I would love to have some insight as to how you do it.
Well, I have only run part of WLD, so I can't say off the top of my head how it's challenges compare to what it typical of mine. I think the main difference could be that I actively tune my challenges. CR/EL will get you in the ballpark, but I take note of what types of creatures fold like a house of cards and which sorts of creatures/spells/abilities/immunities the party has problems with.
For example:[sblock]The second game was my River of Worlds game. I figured out rather quickly that a chaos template from Portals & Planes tended to perplex the party in excess of what their CR suggested, but without boosting damage much. The template causes PCs to take the worst of 2 rolls for all rolls affecting the chaos creatures. So if I wanted to make a longer pitched fight, I knew that an encounter with the chaos marauders was in order.[/sblock]
I typically only intend one encounter per session to be potentially deadly. The rest are nuisance encounters intended only to drain resources or let PCs strut their stuff. Typically the nuisance encounters are EL <= APL; the potentially deadly ones are EL > APL. At high levels, players usually have the means to retreat if things go south, but if the damage comes on very rapidly (like the AoW adventure above), that might not be an option.
Finally, I don't know how much this says, but I typically prefer humanoid classed/leveled opponents to creatures, especially for my "final" encounters. I do find that for single opponents, the system over-estimates the EL.