I work in a dermatology lab.  All we cut is skin.  We use a product called 
HALT.  We never have any problems with tissue washing.  We face our blocks 
and let them soak on ice (put a little water on top of the ice to get 
started) for about 15 - 20 min., then we cut our slides, dry them and stain 
as usual.  We pour two of the bottle caps of HALT in Deionized water (or you 
can use distilled) in eack water bath.  I recommend you give this a try.  It 
works very well for us.  Good Luck.

Jeanie Wade, H. T. (ASCP)