Comment by dofm

> But, for example, are those horns (?) necessary for ergonomics?

More or less, yes.

If you "fill" the cutways on a Strat you have a typical guitar shape.

You want the upper horn there or somewhere near it because the upper strap lug needs to be about there for balance, but some players (especially those with bigger hands) will want their thumb to be free from being blocked by the top of the guitar while they are playing the higher frets, so there's a cutaway. You then want the lower horn to have some of the classic shape below it if you want the guitar to be playable sitting down.

The slope across the top corner of the Strat beyond the bridge is there so that players (in particular guitarists who wear their guitars a bit higher with the fretboard pointing more upwards) don't have the upper arm of their right hand leaning uncomfortably across the edge of the guitar.

Some of these elements were protected by Leo Fender's original design patent, I think, but I can't remember which.