I'm going to try to explain my thinking on this, so if you don't have a clue what I'm on about - I understand completely!!!! :)
The teams run a camber on the wheels so that during cornering, the loaded tyre effectively has all its tyre tread/face in contact with the road, accounting for the deformation of the tyre wall caused by such load. This gives the maximum grip in the corner. However, with this camber, when going in a straight line and not under great load, the part of the tyre that will get most wear is the inside shoulder. Spa, because of the speeds achieved along the straight immediately after Eau Rouge and with the added effect of DRS and KERS, the loads under speed in a straight line are increased.
I would guess that Newey knows his car better than Pirelli, and I'd guess Pirelli know their tyres better than Red Bull, so who is right and who is wrong?
Did the blistering of the tyre actually affect the construction and thus integrity of the tyre?
Only Pirelli will know that, and given their concern, you'd have to guess that it was an issue.
What we need to know also is - did other teams, with less severe camber angles also suffer the same tyre issues (albeit to a lesser extent) - again, this is something we don't currently know.
In conclusion, and in response to Bagwan's opening point, you'd say that, if (God forbid) one of the RB pilots came a cropper in Spa as a result of tyre failure, then the blame would be laid squarely with the team for running a set-up against Pirelli's advice.
It is a tough question, because who is to say that, by running a lesser camber angle, the RB car might have posed a greater danger to the integrity of the tyre through Eau Rouge. We know just how much downforce that car runs, and given that DRS was banned in Eau Rouge - maybe they had to run that angle for qualifying, and did not want the pit start penalty for the race?
Ifs and buts I guess.
One final point, given Newey's sensitivity to safety - after all, it was his car that was carrying Ayrton when he died - would he really be that dumb to put himself in a position?????