Pretty hilarious. I've never read Penny Arcade, but those guys have to be pretty awful...
I played the game on normal. My first death was to those giant beetles in the forest after the prologue, because they can move- and charge- right through each other like it's a bloody MMO.
The arbalest is simple for the same reason that all human opponents in the game are simple.
At that point in the game, you have the stamina to block twice. All foes swing for you the moment they come into range, so the trick is to whack on your chosen target until another one closes on you, switch to E and send them reeling, continue hitting your prior target, repeat, then switch to rolling until you have stamina enough to block again.
There. Finished.
edit: You `will` have to pan the camera towards your attacker and give the nearest movement key (relative to them) a tap before you block, because you won't have the trait allowing you to block incoming attacks from anywhere, but again, an average player should be able to pick that up before they get killed.