You can argue this in either direction until you are blue in the face.

The issue in my mind is that depending on exactly what it is you are measuring from a physics standpoint, there are several different calculations for kinetic energy. The one we commonly use in archery is v^2m/450240..... that is twice velocity in fps times the weight in grains divided by the constant 450240.

I have read people both on here and on AT write dissertations about converting fps to mps or mph or mass to kilograms or some crap like that. Long and short of it is.... you can do whatever you want.... just so long as you do it the same for each bow/arrow you test... you'll arrive at basically the same result... plot it on a graph.... it'll look the same either way. Its just an even comparison.... kinda like IBO speeds are supposed to be.

All you can use kinetic energy for is an equalizing guideline.... it takes a produced speed with a given arrow and assigns it an arbitrary number that corralates with performance.... or potential performance. Based on that, you can make an appropriate choice of broadhead for your situation. Its like a stupid personality questionaire... I don't need a ten question survey in glamour magazine to tell me I'm sarcastic and cynical... BUT just how sarcastic and cynical am I??? Thats kinda how it works....