I too use the torch/low light technique. When I do it, I try to get to them after about 3 reloadings and then keep loading until the necks start to crack (maybe 10 total loadings, plus or minus) or until I scrap that lot of brass. I think that it extends the case life but thats just my opinion. But it surely can't hurt. As for accuracy, I haven't seen a drop off but don't figure annealing will improve it much. The problem with this technique is consistency with both temperature and eveness of applying the torch flame. I don't figure either is perfect.
One thing I'm going to try next time is to not quench the cases in cold water, but to just drop them in a pan and let them air cool. I don't think that the quenching does anything to improve the annealing process and when you do that you have the task of drying them before you can load.
Jim