Interesting. Really seems to point to FOC as the primary variable...

Most mechanicals and the Slick Trick are pretty short lengthwise, most like field tips. Other fixed blade heads are much longer, probably affecting FOC. Probably not as much of a big deal if using a drop away, but add a set of fixed prongs to the equation and the arrow could flex differently based on the different FOC causing a different impact point...

I wonder if using the Satellite Match Point field tips would yield same impact points with longer broadheads? Would be an interesting test...

5 Shot, in your testing, is it possible for a fixed head to score a 5 in your accuracy testing? I noticed 5 means flies like a field point under ALL conditions. Assuming you include wind and possible wind planing from a fixed head, does that automatically kick every fixed head down to a 4? In other words, barring wind, etc, in your testing a fixed head with an accuracy rating of 4 flew just like and impacted in the same place as your field tips?