Man, I got a couple of my farmable medals into 20/21% guilt but a part of me wants that max, lol.
Gonna stick with those and leave it at that.
Chance of guilt percentage increasing drops considerably the closer you are to max. Because each roll ignores what's already on there, so it'll go and more likely land on a lower percentage as a result, which means your guilt won't change at all. Wasted roll.
So nah, don't bother.