RE: Dihedral question
Thge 'Diamond' stabiliser section is much older than Kirkland or Kazmirski, and goes back beyond the 'Smog Hog'. It was, originally, a F/F way of making a symmetric, stiff tailplane simply and lightly. It was only after R/C was fitted to the elevator nailed on the T/E that modellers started to ascribe several other attributes to the section, though I cannot tell any difference between the usual sections used on various models. Not in flight, any way.
Evan, WB #12.