How lucky for you, I've actually seen some too. Every doctor has at least one old geezer who does everything wrong, smokes, drinks, eats junk food and lives to be 100. But don't try it at home, folks. What we are going to be talking about are the majority, and especially the ones who really react badly to the surgery. The surgery can be a painful procedure with a long recovery.
Cats often reinjure the toes.
Some nails regrow. Scar tissue at the site of severed toes leak vital energy via acupuncture meridians originating there. This depletes chi or vital force. There is often greatly increased stress due to fear of attack. A declawed cat soon figures out it is fairly defenseless.