I think the impact would be better if pic was in focus

Neat image. I also wonder what this would like like with a very fast shutter speed. You really captured the precise moment of impact.

Sorry, but I don't see relevance to the theme here. There is alot of motion conveyed, and transfer of force, but not "weight" particularly.

The motion blur of the axe and the log splitting is very cool, but because the entire backround, consisting of fixed-in-place objects is also blurry, it takes away from what would be a much more effective shot.