Re - anodising alli parts never gives the same finish as the original.
The results are unpredicatable, and you may get a finish you dont like.
doing it again, will have no effect on the thickness.

Iron Brake Rotors
 

Well if they are good enough for moto GP they are good enough for me. Just keep a close eye on the discs and check for cracks.

Mike

JHP have had a few fail on them in the past, and they are not good enough for Moto GP, they use carbon in the dry and cast STAINLESS in the wet, which is what brembo now supply.

Personally I sued cast iron for years and only ever had one set crack and that was on a Norton Commando back in the last century!