At 3-0 it looked all over. He could have swapped Saha for Defoe earlier I think, but at 3-0 there is something to be said for not being completely overrun. I remember United trying to hard when behind against City and absolutely getting spanked, or Arsenal against United, taking off their only defensive midfielder and getting shredded.
We outplayed United for most of the game, without Bale, VdV, Hudd (and Parker). An almost full strength United side that is.
We were let down by individual errors, Friedel not coming for a cross and Walker not marking Rooney, then Modric getting temporary narcolepsy at a throw in. Incredibly harsh at best, and in my opinion flat out wrong to blame that on Harry.