I spent two years hunting a herd of piebalds. Passed on the old doe b/c one of her kids was heading my way and the little one's back half was completely white. His sister darn near ran me over though and they all blew out of there. That was the closest I got to them, but I got to see them plenty.
Piebalds generally occur in areas with a high deer population. They are not albinos (no such thing as a partial albino). The color variations are caused by a recessive gene. When you increase the deer population, you increase the chances of inbreeding and increase the chances of this and other recessive traits showing up. From a herd health point of view: shoot and fire up the grill!
They are by far some of the coolest animals I've ever watched in the woods. At one point I saw two youngins romping around. As soon as they lost their spots though - well, the ones they were supposed to lose - I considered them fair game.