Gear, the idea of using vise grips to check neck annealing belongs to Ken Light and yes, sounds kind of crude but it does work. Here is a really good article on annealing where what, why, how, when to anneal is discussed. Lot's good tips and cautions.
http://lasc.us/CartridgeCaseAnnealing.htm By Ken Light.
I'd still like to know if anyone has done a side by side accuracy test of annealed brass against virgin brass and fired brass not annealed. The results would certainly indicate a level of success of the annealing.
Rick