Wow, pretty interesting videos. First of all, all I know about the incident are my own work experience, rumors from friends in the industry, a few news briefs, and these videos.
The ETs story really gets to me the most. My rig is very similar to the Deepwater Horizon, and I can imagine being in that position. When he describes the chunks of annular coming up, and found most likely by a shakerhand (guy that mans the machines that separate earth from drilling fluid much like a bunch of big ass gold mining sifts) I can tell you that that is a huge deal. They should have stopped there, but it seems they were under pressure from BP. Believe me operators are always under pressure, but that is no excuse to bypass safety regulations. Also the discussion about how to displacing the well (I think) is the most important part of this event. There is a procedure called a negative test on the wellhead that is NOT required by MMS (but probably soon will be) that should have been performed before exchanging seawater with drilling fluid. That test would give an indication if the well was flowing gases, and if it was safe to displace.
From the beginning I have thought that the only way this could have happened is if multiple things went wrong all at once, and if multiple people did not do what they should have been doing. I think these both happen to be the case. There seems to be a dozen factors that all contributed and could all have stopped the incident from happening. Also I think it is pretty amazing that all but the 11 people directly affected by explosions lived.