ancientgamer: It's possible to acquire both the magic power move (enemies slow down) and the group finisher move from the sword skill tree - just be careful where you spend skill points instead of just plinking them down willy-nilly.
In general, once you have both skills, a full adrenaline bar, and at least one enemy within sword range, activating your adrenaline moves will first kill off up to three enemies, then activate the slow-mo sphere.
The combat mechanics among groups are downright annoying, and I'm happy I accidentally ended up focussing on adrenaline generation and the magic/sword tree end skills, as the Signs are all greatly reduced in utility in groups of NPC and the enemies will insta-flip to face you even when being attacked by multiple friendly NPCs.
Without the ability to take out a healthy number of foes at a fairly steady pace (on Normal difficulty, with a few +5% adrenaline mutagens, I found I was generally able to chain the slow-mo effect so that just as the previous effect was wearing off, I had a full adrenaline bar again), group combat would be a completely frustrating mess. Friends block your signs, the autotargetting swiches around wildly, and getting surrounded by enemies and/or friends means almost certain death. Couple this with long chains of "dramatic" fight sequences where saving is not allowed, and I can easily see players quitting out of sheer frustration.
I'm glad I bought The Witcher 2, and I hope those involved make bank - but I also hope they'll re-examine the collossal screwups made with TW2, particularly those issues which TW1 had handled just fine. If TW3 ignores such issues or makes them worse, I won't be buying TW4. :P
Well shit, what insane adrenaline combo would happen if you unlock all the three ultimates.
Also, it seems you are much farther than me in-game, and I wanted to ask whether there are Vitality Regenration in Combat inducing mutagens, since I didn't have Melitele's Heart (Darn Newboy, I don't need your stupid Dragon book, and yeah I know I could've killed him or convince him in the prologue to give me the amulet) and if I screw up and didn't drink any potions, I can't just roll around to restore Vitality.