My brother N law splits that way and is very efficient at it!my uncle always used a double bit axe and he swung it so it struck at about a 30deg. angle, weight of the second bit did the exact same thing. it was fast but hell on your wrists.
Also had a friend who split that way to. Made it on Ripply's Believe it or not for his splitting abilities. He had a huge firewood business. This is where I first saw a Super Split, he wouldn't use a hydro splitter if it was free. Goggle 'Tom Clark firewood splitting'