Those could possibly explain it. There are multiple BOPs (aka valves), though, so damage to just one wouldn't necessarily prevent closure of the well in an emergency.
Really? The one he was talking about was right where the well came out of the surface and into the water (at least that is what they were showing in the animations to explain what he was talking about). Either way, it was on 60 Minutes so it could be biased against BP, and technically inaccurate.
Like I said, I don't know the details and I haven't seen any of the animations, and nor do I know if they are accurate. But your description sounds strange to me. The BOPs I was talking about are always right at the point where the well breaks the ocean floor, and there are usually several diverent BOPs or "valves" as part of the larger assembly, which on land is usually collectively called a "christmas tree" (maybe the same underwater - I can't remember anymore and I was a service hand anyway, not a driller). As part of the christmas tree are several different types of BOPs. There are "blind rams" that shut the well off if there's nothing else in the way - like drill pipe. There are "pipe rams" which fit around the drill pipe and seal off the well when the drill pipe is in place (but does not seal off the inside of the drill pipe). There are annular BOPs which are similar to pipe rams, but more flexible - i.e. able to squeeze around odd shapes, such as pipe joints or other things like drill collars. And there are also shear rams, which in a major emergency can cut through the drill pipe and seal the well.
And all these separate BOPs are attached securely to several concentric strings of steel pipe or "casing" which are securely cemented into several hundred or thousands of feet of rock, by the time a well reaches the stage at which a blowout occurs.
And on top of all of that, these BOP types are also duplicated at the surface, on the dilling rig itself. And, when people like me would arrive to shoot holes in the casing to unleash the unrestrained well pressure, another, triply-redundant set of BOPs would temporarily be installed at the wellhead.
The few things I have seen in the media are oversimplified. I am really interested to read an analysis of what happened by someone who actually has the facts and knows what they are talking about.
Here's a good photo of a seafloor BOP system with multiple, redundant rams:
...but with large companies you also usually end up with it taking several weeks to get anything done regarding maintenance... I wonder if that did play a part.
That's the interesting thing about private industry. I got to see EVERY major oil company in action, at intimate distance, with the glaring exception of BP. It was amazing to me how different they all were. Some of the biggies were truly amazing, efficient, well-run machines. Things got done instantly, purely on the authority of experienced people in the field who had the authority to make decisions and spend money, no questions asked. I don't want to name names, but I wish I could, because this company was the best. But there were also a few local offices of other big companies that ran similarly smoothly, but other offices of the same company weren't nearly as efficient.
On the other end of the scale was a giant who has since gobbled up many others, and it was run almost as inefficiently as a federal government agency, it's field managers had no authority to take actions, it took weeks to get something decided, etc. They were not the best to work for.
And I also saw everything else in between.
But, like I said, BP was probably the only major that I did not have any experience with, so I have no feel at all for what they are like.