Pumping mud is just eye wash to make it look like they are doing something , evidently from what I’ve read the last thing they want is to suddenly plug it, if they do , it will blow out farther down and the pressurized oil will just be more out of control, possibly making a relief well impossible
Just read at the New Orleans newspaper site that they are going to be inserting tennis and golf balls as they are changing strategy.
http://www.nola.com/news/gulf-oil-spill/index.ssf/2010/05/top_kill_strategy_to_be_adjust.html
People are expecting it to blow sky high from some of the comments. BP has by far the worst safety record of any oil company yet ZERO allowed them to stay in charge. Seems 97% of major safety violations belong to BP. That must have been some amount of money BP donated to Obama and the Democrats.