ORIGINAL: highhorse
On many twin-boom models, like the KC and Reaction, the engine eflux is so close to the horizontal stab that the accelerated airflow causes a low pressure area underneath, pitching the nose up more and more as power is applied. When the exhaust is pointed down the effect is to create a thrust-variable counter'force to this problem.
That's what I hear too, but my Reaction X and a friend's Reaction 54 (kit) have a single empennage (sp?).... unless Bruce snuck a twin boom out on the market without telling the public.
