I've done searches and what I read tends to be about whether or not broadhead tuning will help or not. What I would like to know is the best way to heat a carbon shaft to tune the broadhead. Also, I've read to place the blades inline with the fletching. It seems to me that would be ok for a straight fletch, but wouldn't it be better to stay in helical aliagnment with an offset or helical fletch?

You should not heat up a carbon shaft. This will melt the reson in the fibers and weaken the shaft. I use washers to tune my broad heads.

http://www.broadheadtests.com/TUNING.html