I figure the grain is still straight, even if it's corkscrewed around the trunk.
Remember, you don't need the edges to follow a grain line along each side, but you do need to be able to establish a centerline with enough meat for your design on either side.
I start out looking to peel off long rectangle-shaped pieces, no shorter than 36".
I envision a thick strip of straight-grained wood wrapped around the trunk. Unwrap it, it's flat.
I mark out my lines along the grain. I first mark up all the longest clear billets, then mark the short pieces to be splice limbs.
Then I get busy with my circular saw. I begin with a shallow 3/4" cut, then make deeper passes until I get it deep enough. I'm probably going deeper than I need to.
The first tree I cut yielded two 6.5' logs. Each had its knotty half, but i loaded em up as is.
Then I spotted the one I'm working on here. Just the bottom 6.5'. From this log, I split off the knotty side and left it in the forest. I used a chainsaw because I didn't feel like f@&*in around.
The bark peels off easily this time of year, with a hatchet to pry it off a little at a time. Get that off, and you can see the grain clearly.
I got 3 long billets and three short ones I can use for splicing. Plus the heartwood, there's definitely a stave in there if I want to ferret it out.
In my experience, the twist will come out easily with steam.