You have all confirmed what I suspected. I just like to check around to see if my instincts are right. The greatest fear, I gather, would be that the flushing dislodges something that plugs a gallery or port, etc. thus destroying the engine. In that I just bought an old M-B, I thing my best bet is to change oil very frequently for awhile and then keep synthetic in it. I'll change oil immediately, then at 200 miles, then at 500 miles, then at 1000 miles and replace with synthetic.