Clearly this is not the discussion I was looking to have. So I'll just go ahead and stick my neck out here and maybe we can have some dialogue. First of all I do not believe that optimal broadhead flight is acheived by getting the broadheads to hit with field points in the vast majority of cases. The geometry of the fixed head will have a different affect on the arrow spine than will a field point and unless the spine is so stiff that the difference is negligible the POI for optimal broahead flight will be different. I do think that comparing broadhead groups to field points does give some useful info regarding the setting of the nock point, but that's about it.

I think that the optimal way to tune centershot on broadheads is using the walkback method or some such equivalent method. Personally I like using a 20 and 40 yard distance going back and forth till the horizontal POI is set.

I think that the previous gold standard of getting broadheads to hit with field points was close enough because the bows were not generating the speeds that todays bows do. I think this is no longer the optimal way and I think that this will only be amplified going forward by continuous improvements in bow design and materials.

If you don't agree with my position then state why and give me your rationale and tuning method. But I want details. How do you determine adequate spine? How do you set the nock point and centershot for optimal broadhead flight?