Speaking of Neanderthal... my first experience with cutting down a prop was extremely crude.
I had a brand new Fox Q500, with the tuned muffler, back in about 1986-7, on a design of my own.
Couldn't get it to really come up on the pipe, but the plane was flying nicely. One of those
guys who shows up all the time, but doesn't have his plane ready right now tells me that
my prop was too long (which I knew, but I'd never cut one before) and that the way they used
to do it was to run the engine up, then alternately tip the plane forward into the concrete or asphalt,
shaving the prop down... then back, to see if it would come up on the pipe. Rinse, lather repeat.

To this day I can't believe I did it, but I did. I finally got the thing up on the pipe, too... but the prop
must've been BAD out of balance... because I lost the crystal, and of course, the plane, the receiver,
and the brand new Fox which was probably only about half broken in. (Along with my 18Yr old wallet)

Sure did scream like a **** for about a minute and a half though
I don't cut props down these days, without rebalancing... and I learned to tape my crystals in place, too.