Place the straps in approximately 2 cups of warm water add 2 little blue pills with a V on them and let soak for 2 hours. Air dry and if the straps are too stiff to bend after 4 hours consult your bike doctor. - sorry couldn't resist after seeing the thread title.

Seriously - I've used Glycerin for soaking furniture caning and it will shrink and stiffen the cane after it dries but I don't know if it will have the same affect on leather. I can't speak for the VO laminated straps but I have a pair of their standard leather ones and they seem like they should hold up pretty well and are more comfortable than other straps I've used.