(35 degree bevel on iron plus 20 degree plane bed).
NOTE - this cheap imported caliper is zeroed at .001" - i forgot to change it for the pictures - all shavings are .001" less thick than the indicator says.
max comfortable shaving – 4 thousandths. This is a gamed test, the wood was already cleanly prepared with a Stanley – so no guessing as to whether the wood is tearing out. It’s easier than starting with rough wood and getting to smooth. I think it's probably also easier for a plane to maintain tearout than remove it, but that's something for another time.
At 55 degrees with any appreciable thickness, you get holes in the shavings and these little innocent looking light brown tearouts. They are several shavings deep, though, and broken apart. If you go to scrape them out, it takes a long time and you will see a divot. Pictures of the tearout spots plus what the shavings look like with holes - holes in a shaving several thousandth thick indicate big trouble if you're intending to finish a surface.
Lighter shavings may prevent this but they’d be light enough that they’re not practical for anything.
This also is still in agreement with something I did with this piece of wood 8 years ago - plane it with a 55 degree infill with a tiny (.004" at the time, it's now .003") mouth - I couldn't chase the tearout out of the surface no matter what and sharpening was constant to try to do it with thin shavings. absolutely unworkable. I almost planed it cleanly with a stanley at the time - before I even completely learned the cap iron - but not quite. I declared it a pain in the ass and put it aside because it would make nice handles perhaps fingerboards where the other side of the billet doesn't have a wrinkle/reversal.
Nobody (no hobbyist, typical furniture maker) would make a large furniture piece out of wood like this, and in the world of guitars, it goes through a drum sander, gets its pores filled and is then sealed and lacquered if anything. It's very aromatic and sanding could be troublesome for some, but planing it just makes shavings and a little bit of filthy fingers handling it.