Possibility to inverse the "PlayerMustcrouch" logic?

[rpfurlong]

Currently, PlayerMustCrouch=1 requires crouching, PlayerMustCrouch=0 works with crouching or not.

Would it be possible to have the inverse logic, like vein mining when not crouching, but precise single block mining when crouching? Would be incredibly useful when standing on vein blocks above an abyss. :)