Hawkeye, yes a beltsander would work if you could find away to hold the leather on a flat surface. You might be able to use barge cement and then rub it off the surface grain, it may not hold on that slick surface though.
J, check around someone in the shoe repair industry. Most leather shops have a couple different splitters. Don't let anyone try to split your cordovan in a twist handle osborne splitter, won't work. You need the flat table kind with the ajustment wheels on top.
You can do it with a round knife and sciver but it takes a very trained and steady hand.