As someone who pushed for Koeman, Schaaf and later Sherwood to be appointed, I was completely underwhelmed by Irvine. He was nowhere on my radar. He seems to have prioritised getting defensive players in, some of whom we saw today. That would seem to fit in with a philosophy of setting teams up not to get beaten.
But, I will withhold a verdict on him at least until we see Valera, Blanco and Samaras, and you have to allow new players some time to gel as a unit. That's if he uses them. We have to see what the balance between defensive/holding players and creative/attacking players will be.
However, the signs are not good. Its not that we just were beaten by Swansea, it's how we set up that bothered me. If we had come out and taken the game to Swansea and got beaten 3-2, I would be more hopeful. But we set out to contain Swansea with too many similar players and nobody able to make runs forward behind the Swansea defence. Except for Sess, by which time the game was lost.
Also, I hope that Irvine is not going to blame the result on individual errors. Errors are made by all players at the highest levels. What he has to look at, is how he sets the team up, to contain the opposition or go out to win.