The discussion of incidence in Ben’s referenced article, dealing with trimming of rubber powered free flight models, is only marginally relevant to radio controlled aircraft with adjustable trim and elevator control. First there is the definition of incidence. The article defines it as the “angle between the wing chord plane and the tail chord plane”. Normal convention defines it as the angle between the wing chord and the aircraft (fuselage) reference line. The horizontal stabilizer is normally set to zero incidence with reference to this same line but can have either plus or minus incidence also.

The article deals with balancing a model by moving the wing fore and aft on the fuselage, which changes the tail moment, and adding ballast to the nose or tail which changes the cg. It only implies that there must be some difference between the wing chord angle and the tail chord angle for the airplane to be both stable and balanced (which for the type of model it's dealing with is basically true). As significant as this is for trimming a free flight model, I don’t believe it answers the original question.

On a radio controlled aircraft with adjustable trim and elevator control, if incidence is increased and the cg and tail moment remain the same, The trim must be adjusted a little nose down, which in effect restores the original angular relationship between the wing chord and the tail chord. The airplane will then fly a little nose down in level flight and when inverted will fly a little more nose up. Since the thrust line remains the same the effect is like adding a little downthrust, but for relatively small angles that effect is negligible.

The overall effect of changing the incidence is a change in the deck angle period.