I'm working at a London bike shop while I'm 'between jobs' in aviation. Oddly enough I fitted a new Miche 103mm BB to a customer's repainted Mercx frame a couple of weeks back; I used a brand new cutter on the shell, lots of grease and bolted it up nicely and tight. A week later it came back with the r/h cup unwound and jammed up against the crank. Not good. So I whipped it all out and had a good look at it, just a bit of scuffing around the r/h crank but nothing more. I'd not heard of mechanical precession in relation to BB's, only regarding gyroscopes in autopilots etc, but it made sense when I researched it. So I did as others have done - cleaned the excess grease off and refitted it and so far it's been ok. Interesting stuff.