hydrogen leaks

There's an interesting theory over at All Things Nuclear - Link - about the hydrogen explosions. Most have been portraying the explosions as part and parcel of the venting process. But the question being ignored is why the fuck would you vent it inside the building? Some have said the operators did it to lengthen the time the off gas lingered inside (and thus amount of radionuclides that decay) before going into the atmosphere. Perhaps.

But what ATN thinks happened is that the top of the reactor known as the drywell actually lifted off its moorings enough to open a small gap to allow steam (and hydrogen) to escape. It happened during a test at a US power plant under much safer conditions. It's a little bit frightening to think the primary container on the reactor could really be breached that easily. But if it's true it allows the operators to vent safely in the future. Namely don't let the pressure get as high as it did before.

The only potential flaw in this theory that I can see is that at the test plant the pressure stabilized (because the reactor was leaking).  If the containment pressure stabilized I would think the operators would not vent.  That they would wait for it to hit some predetermined point.  And it seems unlikely that those two points would be the same.  Interesting nonetheless.