I've not had the expansion long, but it seems to me the main danger to my characters is when an opponent uses (Greater) Whirlwind. It seems to be more or less the uber-skill for fighters: my 4 20th level-ish fighters managed to kill Demogorgon in 2 rounds of all using Greater Whirlwind.
The point I'm getting to is that dual classers don't get the high level fighter (or whatever) skills that multi-classed characters get as soon as they pass 3,000,000 XP.
Any thoughts? Will the multi classers return to power once again?
PS to whoever said that their multi class F/M couldn't pick Dragon's Breath, etc at level up, you have to be able to cast 9th level spells to pick those. ie 18th level in your mage class. You can pick *all* the fighter abilities the whole time though... mwahaha...!