So not that long ago, we are at Ethans, and we are setting up for the gathering, and I see the usual shuffle to find the right spot, and I see someone bust out a BK20 to cut down some small saplings that are in the way of their hammock. It is a huge knife, and it is not light like the BK9, and they struggle with it a little because it is so dang big and so dang heavy. They weren't cutting down a six inch thick tree, they were cutting down three quarter inch saplings.
I have cut down a six inch tree with a BK9. I have cut down three quarter inch saplings with a BK9. Neither was difficult, or strenuous. The BK9 wasn't unwieldy or difficult or tiring to use.
To me, that is why the BK9 is king. Because it is the right amount of knife for the job. It isn't too much, it is the right amount.