I've used them on GoldTips and ACCs and the overlap has not made a significant difference. I was shooting out to 70 yards this weekend and getting 6 inch groups so I can be fairly sure that they aren't affecting the flight.

I do not know what chemical would be used to remove them or why it would be needed. Just cut a strip of the crest away and it peels off fairly easily. Much easier than stripping fletching.