Spray adhesive and double sided, can be a real pain to remove after a while. I have some 12mm float glass, and getting adhesive off involves scraping and scrubbing with dedicated adhesive remover solvent.
In the case of the Hermes self adhesive film, if you do not remove all the hardened residue when you refresh the film, you get bumps that transfer through to the abrasive face. Yeah, I knew that, and still neglected to do a full clean a month ago, so this is fresh in my mind!
Tip for sticking down abrasive paper.
When using normal abrasive paper, you can help with the clean removal of double sided by using 14-day masking tape (I like 3M blue universal 2090 tape, but there are others). Masking tape on the surface, then the double sided, then the abrasive paper. The double sided is much cleaner to remove off your glass, varnished wood, Corian, Tufnol, etc sharpening board.
While 600 and 1200 are the most common range for sharpening, I fairly regularly use 220 and 400 for repairing badly dinged edges, or re-shaping bevels that are too obtuse. Someone uses a Mora to cut bacon against a cast iron griddle, you don't want to be taking the damage out with 600. Roll out 120grit! Also, if you are trying to take a 40deg edge to 28deg, it can take a very long time with 600grit.