Most times people never see thier finished work, when they rolled un fleshed pelts and freeze them up. Most of the damage can be doen in the center by the time they pull the pelt out in as little as 3 days.
One won't see the damage on thier prepped pelts as the hair won't generally fall out when working the pelt, but once it's put into the tannery process and re-hydrated the hair starts to fall out from the most heated spots or decayed areas first.
Mostly where the pelt was rolled, right in the center of it, this can range from mild loss to actual bare hides, bellies first, then the flanks and if really bad right into the backs.
Fur should always be laid out flat for quick flash freezing, then placed in some sort of paper bag or plastic after it's frozen to help prevent freezer burn. Thaws out quicker as well this way.
Now I know this comes up lots of times during the season, and many have rolled thier pelts, with out seeing any bad things happen, however most of those never have the pelts come back either and really don't actually know what happened to them.
Freezing flat will probaly get you more pelts in the freezer as well, I know it does for me when I need to do it.