>>2827765
Train up hike down isn't the way I would have done it, but still sounds like a great trip. Looks like you got an awesome weather window.
I (>>2822517) did katahdin a few weeks ago taking cathedral up, going across knife's edge and down helon taylor. If you talk to the rangers, they'll tell you not to try descending cathedral which is 100% correct, its absolutely brutal going up and uniquely unsafe to go down. There's a couple of cool boulder caves you can squeeze into on the trail though, when I was there the temperature inside the caves was cool enough to see my own breath even though it was in the 60's outside.