Interesting method, but have you tested it with templilaq ? Seems like it would get to hot to hold before the neck and shoulder got hot enough. Bet your fingers smart after doing 50 or so.
You're right, if you hold each case in the middle until it is too hot to hold your fingers will acquire a bit of a sunburn. So I quickly learned an alternate way to do that.
Count the seconds it takes for the first 2 or 3 to reach "too hot to hold", which is not a test of pain endurance, just too hot to hold without burning your fingers. That time will only vary by maybe a second from case to case. Once you've established a baseline you can hold the cases by the head and just count how long to keep them in the flame. Or use a socket of appropriate size in a drill or electric screwdriver to hold the case and rotate it in the flame.
