There have been plenty of human blunders, everything from boat handling (foiling when they don't want to, coming off foils at the wrong time, blown tacks, slow gybes, poor roundings, etc.) to bad tactics and strategy.
The technology just makes the boats so fast that the human mistakes can crush you. Of course, the same happens with the slow boats, but the distances aren't quite as magnified.
Jonson's best quote of the last few years (still not sure of he meant this as a compliment, BTW): "Match racing on steroids!"
EDOT: Relative to monohulls, the pre-starts have been pretty boring. No dial-ups, chasing each other through the spectator fleet, etc.
