Humbolts are also easier to do, and are more forgiving regarding dutchmen and other such errors.
Conventional faces are easier to teach, so it's a good method for learning, but much harder to match corners up. Also, when cutting rotten, burning, or otherwise compromised wood, cutting the angle before the gunning cut can sometimes save a pinched bar. That's one I would much rather have learned from somebody else than on my own, on a fire. I ended up pulling it through on the dawgs, no face, no holding wood, and just watching the top when it tipped and skedaddling to safety. It was pretty hairy there for a few moments.
Open-face notches really don't have much place in my world, except for when I have to bore the face of something small with a heavy lean and I want to get a wedge in back. In that case the bigger opennig can be a help.
