It helped with going to the belly on knife edge...not seen much today....but an incidence change (increase) and c/g adjustment gets the same effect...and is likely the best way to fix it.
In fact...I flew the brown Scepter quite a bit and it flew much better than my straight stab until I added incidence and adjusted the c/g....then mine flew as well or better.
Brian Hebert has a great white paper on trimming called Triangle Trimming....it's very good and easy to understand.
Highly recommended.
In fact....I found that I really didn't know much about trimming an airplane until I actually did it in a couple of moves using TT.
It really improved my F3-A flying ability on the 2mtr electric airplanes.

Dave