Thirty-thousand horsepower pumps with high pressure drilling "mud", injected into the system, backwards. That is a lot of pressure feeding into ruptured pipes, which they think may be holding back the maximum flow. Could it make it worse? I'd say the possibility exists. It's an unknown.
As I understand it, the system failed on the well sealing process, when a cost savings measure was introduced: Replacement of the drilling "mud"--in the upper third of the column--with water to speed production. (It seems to me that "savings" were the whole idea behind the projects, at the expense of something you cannot put a price tag on.)
I'd say their "mud shot" will be met with failure, as well: Now you are resisting a high pressure flow on a source thousands of feet below the sea floor that has momentum.
Yet, BP has resisted scientific involvement, and even threatened reporters attempting to document the spill with arrest.
BP says there is no way to measure the flow, and that is a lie. We've had doppler radar since 1988, and I know doppler sonar would work; you can hear the difference in engine noise as they drive past. Doctors use the same tech to monitor cardiac conditions non-invasively. Yet they are not allowed in.
I'd say that the failure to release information should fall under Obstruction of Justice. Though I am certainly hoping that the courts are working hard to make an example out of these donkeys.