Not exactly an aerobatic maneuver. The pilot made a a fundamental mistake when initiating his turn. He had established a level minimum altitude. When he began the turn, he should have pitched up initially so the low wing never went below that minimum altitude.
I can't agree with this. It makes some assumptions that may be quite wrong. You say he established a minimum altitude, but did he? He leveled off at an altitude, who's to say his level altitude didn't have some "fat" built in to allow for his turn? This is a discussion I've heard before, some agree with you and say you should pitch first then roll, other very experienced low level fliers have countered that it looks a lot better if you roll then pitch and provided you're at a reasonable altitude to start with, it's perfectly safe (personally, when I used to do this sort of thing, I'd pitch then roll but I have no problem with pilots doing it the other way.)
I have commented negatively here before about the TAP low pass. My own comfort levels tell me that the TAP pass is not ok and this B747 one is, YMMV of course.
If you think rolling prior to pitching indicates inexperience at low level flying you must think the Red Bull Air Race guys are a bit wet behind the ears do you?