As stated before, the video is from the embellished part of the storyline told by the fat dwarf, where all darkspawn practically die in one hit (or blow up when FemHawke sneezes at them). The player in the video didn't even pause the game, giving the impression of a straight-to-bargain-bin slasher.
If the first gameplay video of DA:O would've been the battle in front of the Denerim gates, where legions of darkspawn die in one hit as well, reactions would've been the same. I'm curious to seeing an official gameplay video featuring a non-embellished part; two-handed sword animations better be not as slow as in DA:O.
And on another note, Lair of the Shadowbroker reveals that Garrus suffers from some pretty major mommy issues. Nobody escapes Freud in a BioWare game.