If you don't mind, can you give some details on your broadhead tuning methods? Because what you're describing isn't my experience at all.
After finding out that they were so much less trustworthy than expandables, I went to bare shaft tuning of them, first trying the shaft with field points and then with the broadheads. This consisted of tuning by finding a nock setting that the shaft liked and hoping that the broadhead liked it too, which often wasn't true. Shooting the broadheads into targets showed me that some heads couldn't be pulled (they shot decently once). Some heads were spun before and after the shot which showed a difference and I made the assumption that it was the pulling although it could have just been the inpact. Don't know, don't care. I shoot a No Cam and an Excalbur Matrix 330 so tuning the bow only consisted of adjusting the rest on the No Cam. I did get Thunderheads and Muzzys to shoot OK in both, however, if they didn't shoot well I didn't try to tune the crossbow arrow if it spun well because all that was left then was refletching, obviously a slow and less likely to find the best position method.
The worst were NAP deep 6s. I tried a bunch in the No Cam, wholly unpredictable.
