These strops can take some abuse. I believe shell cordovan will not show crease marks if you ever wanna bend it or roll it up.

My memory is lacking but instructions say that you can use a wet towel to add water to the strop but stop before the discoloration reaches the back.. I think that might be related to cleaning it..
I have done that and i have used Leatherique to remove the metal from the strop . It is a product for restoring old leather car seats where you saturate the leather with one product over a few days and then use another product to remove the filth..

My 90000 is super soft and slick but shows some swarf..I did recently buy a spare one to store in my cupboard forever, i think i will check on it after reading this thread.