The head needs to be ground down with a file. Sharpness is for knives since knives do a lot of slicing. With a axe its a wedge so a thinner wedge is going to go deeper than a thicker wedge. Kevin Kevech just did a great video on axe grinding. Try taking the hultafors all the way down to 15 deg, I promise you it will completely change your chopping.

Great to see you mod your tools and experiment. If you haven't already seen it, you might be interested in "Skinny Bear and the Dogs" YT channel, has a series on modding the GB AFA. Keep up the good work!

Those Swedish axes are made from some hard steel! School has been tough in the last few weeks so haven’t commented on vids for long now. I have a small advice for you about the american felling axe, if you want even better performance, try to thin the whole convex a little bit, for some reason Gränsfors likes to make some of their edges kinda fat. It is probably because Sweden has softer woods, but since I don’t live there and I rarely have the chance to chop softer woods, I don’t know for sure. Strange thing is that my AFA didn’t need thinning because it was perfectly fine and was thinner than other people’s. Good video as always my friend!