PDGA said:802.01 Discs Used in Play
C. Players may not make post-production modification of discs which alter their original flight characteristics. This rule does not forbid inevitable wear and tear from usage during play or the moderate sanding of discs to smooth molding imperfections or scrape marks. Discs excessively sanded or painted with a material of detectable thickness are illegal. See sections 802.01 D, E and F
Apothecary said:this notion really interests me. it seems to me that the clutch point is whether or not the flash is considered (by the manufacturer) a mistake or not. if it is, its ok to remove it and make the disc fly "as intended".
if its NOT a mistake (and i havent seen anything to suggest that it was a mistake/defect) then its illegal to willfully remove it.
thats just my understanding. if there are people reading this who are more familiar with the rules and how they are enforced, i would love to hear your perspective.
As for the manufacturer's view, just ask them whether they would prefer a manufacturing process that leaves non-design production remnants on their product, or one that does not. I file flashing under "imperfection".
I don't think tire manufacturers would leave those tits all over the sides of their tires if there were an affordable alternative either.