The science behind it is..... actually not the sleeve expanding and a looser fit, it is in there at the same fit, because the piston also expands and is engineered to expand at the same rate. its is much easier because the metal is softer and can be compressed easier. It is completely normal and not to be worried about.
and yes, very good newbie question, i am SOOO sick of "can i stick a os 30 and a 12 speed in my evader?...."

Dann