I still disagree with the technical point about top kill and pressure.
There is pressure in the well now, a static pressure because the well is sealed. It is about 7000 psi. That is the limit the resevoir is able to exert through the weight of the oil from 18,000 feet to 5000 feet. Someone has calculated what this puts the pressure at the resevoir to be, I can’t find it so lets just pick a number, like 12,000 psi (which would be true if the oil in the well weighed 5000 pounds per square inch of pipe diameter, I think).
If I now want to push mud into the static well at the top, I need only to exert slightly over 7000 psi at the connection, and mud will begin to flow into the pipe. Now, that mud will be heavier than the oil, and will begin to sink. Not very fast, but it will sink.
But the mud will also displace oil back into the resevoir. How? Because first, when I put mud into the pipe, since fluids are incompressable, oil must go out the bottom. And I can do that with about 7000 psi of pressure, because the mud that I trickle in is heavier than the oil I displace, which actually helps LOWER the pressure at the well head.
(I am ignoring the fact that there is gas in the line, and that gas is compressable; I ignore it because to the degree we simply compress the gas in the well, we also add a lot MORE weight to the stack, and lower the pressure at the top of the well by that much more).
After a short period of time, we can pump more mud into the top, because the pressure will drop. Or more likely, as we exert a constant pressure of 7000 psi, mud will flow faster and faster as the heavy mud displaces the oil back into the resevoir.
So I don’t see this as a big risk of blowout, nor do I see any reason there needs to be an oil flow to make it work.
Moreso, I don’t think the info on the casing pressure is valid. Because if the pressure is 7000 psi at the top of the well, and that is just at the max pressure for the casings, well the pressure is higher a thousand feet lower, and even higher as you move down more, and it’s the same casings.