The biggest error was playing him in the middle when he was actually a dribbler and not a passer. Especially considering his physical stature. He's a small player who skilfully dribbles past challenges, being placed in the very center of the park which has the biggest and toughest tacklers roaming it, CB's and CM's. A passer of similar stature would have protected himself (Cazorla), because his game is to release the ball quickly. A natural dribbler on the other hand likes to invite tackles and run past.
He should have been protected on the flank, which is where he looked arguably even more impressive, where he would be dealing with relatively smaller fullbacks. You certainly would not have seen McNair come flying in if Wilshere was dribbling from the flank.
When he played in his debut season, he sat deep and very rarely dribbled up the pitch. He also kept a short passing game. When he returned, he was used higher up and suddenly we had Wilshere dribbling through the heart of teams. Can't really envision anything more than a 5ft 7 20 odd year old getting hacked to bits.