I haven't boiled, but I have a bit of a related story...
I set out to clean up an LC-series lid that had various crayon/marker/scuff marks/etc on it - my approach was:
1. Goo Gone on marks, let soak
2. Rinse/scrub Goo Gone in running hot water with sponge
3. Thoroughly wash entire case with sponge and dish soap, still in hot water
4. Use "safe for non-stick pans" scour pad on remaining markings with dish soap until gone
5. Hang from basement rafters with twine for 3 days to dry
I expected a disaster from the scour pad, but this case looks fantastic now. I swear it's de-yellowed, though not completely in the worst area toward the rear. But the whole thing is several shades lighter. I later read about the boiling theory and have been wondering since, but haven't had the time to test another case.
I set out to clean up an LC-series lid that had various crayon/marker/scuff marks/etc on it - my approach was:
1. Goo Gone on marks, let soak
2. Rinse/scrub Goo Gone in running hot water with sponge
3. Thoroughly wash entire case with sponge and dish soap, still in hot water
4. Use "safe for non-stick pans" scour pad on remaining markings with dish soap until gone
5. Hang from basement rafters with twine for 3 days to dry
I expected a disaster from the scour pad, but this case looks fantastic now. I swear it's de-yellowed, though not completely in the worst area toward the rear. But the whole thing is several shades lighter. I later read about the boiling theory and have been wondering since, but haven't had the time to test another case.