You are of course right BOAC and our OM offers alternative methods of compliance (AMOC). If you do not like the crossfeed open you can still use the original procedure.
The TWA 747 is an interesting one, who knows? There are similar Boeing systems issues and it is the only aircraft that actually exploded in the air. You are right in that they spent a lot of time looking at the fuel system. But I think the Thai and PAL incidents focussed them on the 737.
In general the NG stays much better balanced. The classic can be a nightmare and every aircraft behaves differently.