I'm pretty sure I've seen old free flight designs with a lifting tail mounted upside down. I shouldn't bring that up here because it is confusing to the RC trainer issue. The point is the designer either had a preconceived notion that it would do some good.....


or


...he actually tested the design with different tails until he found one that gave his design good flight characteristics.

So, I wonder if the designer of the Telemaster tried a flat stab and had elevator trim issues?

Usually that problem can be trimmed out by raising the rear of the wing slightly.