Theres one school of thought that says that blipping the throttle as you switch off will just leave unburnt fuel in the cylinders..which will eventually wash down into the crankcase.

Might be a good idea to build up some revs and switch off the ignition say for the last five or six trips just before doing an oil-change.......hopefully the fuel draining into the block would get some crud off the rings on their way down??

Thoughts on this ??

Anil