I have a shell cordovan question: I recently bought a pair of Leeds and a pair of Dundees, both seconds and in 8.5D. I started wearing them at home for 2-3 hours at a stretch to break them in. The Dundees developed a couple of ripples on each shoe at the second wearing but the Leeds did not. I have now worn the Leeds for an entire day (out of the house) and it still has no ripples. What could be the reason for the Dundees getting the ripples almost immediately and the Leeds not getting them at all?