I think McCullum is probably a great guy tactically -- his captaincy was really good to watch. I do think the effects of positive intent and all that are overstated. If intent was all that's needed to dramatically increase both your average and strike rate, a lot more batsmen wouldve cracked it. If you have the same conditions, you have to sacrifice either average for strike rate or strike rate for average.
I don't think it'll consistently work against good sides in test match conditions. I expect to see that soon. I do think tactically being offensive in an intelligent way that McCullum showed has a lot of upside, but you cannot simply turn a 25 average 50 strike rate batter into a 40 average at 130. It is possible today and this test match England do this again, but over the long run I would expect a lot more sanity.
I know limited overs batting bucked this trend about 10 years ago(aided by conditions to some extent), but test match cricket is a bowler's game.
If we put 400 up and bowl as we usually do, we are well in it.