. I don't know if the butt grain helps with veneer log value, as Stig cuts them. Seems like stump grain isn't going to make good construction lumber.
The reason for doing it that way is that beech logs like to split from internal stress.
The stump grain holds them together.
Once they've been boiled, they don't split anymore, so they cut the end of the log off at the mill, before setting them up to be peeled.
I honestly don't see the problem with doing the sloped cut first.
Sure you are committed, but so what?
Either you can set a facecut in the right direction or you can't. That goes for either method.
I use a conventional on the ground, unless I have a special reason not to. It is a bitch to try to cut a Humboldt with the low stump requirements that we work under.
Taking a top out or chunking a spar down, I usually go the Humboldt way.