Al
I've tried both several years ago at the request of Henry Childs.All of my old 6BR barrels that I don't give away get turned into 6mm-06 and have 8-8.7 twist rates in them.I asked Henry if the rotation helped them on the explosiveness and naturaly he gave me a test rather than a answer.
I had two barrels chambered up one with a 8.5 twist and the other with a 14 twist both shooting light bullets.
As you know knocking down coyotes isn't a complicated endeavor but when slapping them down is your goal velocity is king in my opinion.
Lynn