Having carried two people out of the woods after mishaps with a chainsaw. I would have no problem justifying shooting on site a threatening attacker with a chain saw.
The first was a guy who tripped while limbing a downed tree and the saw flipped back on to him, severed his left arm.
The second was a guy clearing shooting lanes from his tree stand down to the river, some how he slipped and the saw entered between his ear and his neck, ended up near his sternum, they figured the twisting of his hand with the kickback reved the sawup to the redline and it just kept cutting.
so after seeing that I have no problem thinking a saw is more agressive than almost any other hand held weapon