[Bullseye Disc Golf.com]

I have a lot of experience with this mess and unfortunately it is for many disc dyer's, the "deal breaker" when it comes to trying to do dye jobs in any kind of "production" fashion.

The best product I've ever seen is what sodrifter just mentioned called Rapid Remover. If this did not exist I probably wouldn't ever bother with trying to even dye discs at all. There are plenty of really good dyes on eBay for reasonable prices.

The amazing thing about Rapid Remover is that it's all natural and citrus based. I would never want to use some nasty chemical for hours on end, trying to clean gummed up discs. Regardless of the product, the extra step of having to clean off the goo is probably the biggest deal breaker for wanting to dye discs at all.

Although... in many cases the vinyl just magically peels off with no residue at all.

I think the longer you leave it on, the worse it gets. There's really no reason to leave it on overnight if you don't have to. The quicker you hit it with dye and the quicker you pull it off, the less problems you are going to have. Keeping it out of direct sun and at a reasonable cool temperature will improve the process.