Izzy, I have different thoughts on the broad head field point debate as a tuning issue in regards to different points of impacts.
At close range, 40 or less it is easy to tune the two together for point of impact. At a certain distance they will separate as the broad head loses speed faster because of drag.
I have shot broad heads and field points thru the chronograph at 100 yards and depending on your initial speed the difference can be 10-15 fps between the two. So the broad head will be low.
Once the speed starts to separate to a degree that substantially affects point of impact, tuning or form can't help that.
If you can get broad heads to group with field points at 30 or 40 your bow and you AE doing fine. Don't beat your self up.
Some will say they get theirs shooting the same out to 80 or more. I would contend the size of the group opens up some and an 10" group at 80 is ok for their purpose. But 10" is a lot of dispersion. Bh's 4" low of field points is close enough in their standard.
Just saying your issue may not be you, your form or your tune.