No, it would just act like down trim.

You need to remember that even if the tail incidence angle is less than the wing that this does not mean that it automatically flies at a negative angle of attack. Lift at the tail is related to the direction the air hits it from. If the wing is flying at a high postive angle then the tail is often flying at a slightly lower positive angle and generating positive lift. Push the nose down to pick up speed and then level and trim for the new high speed flight and the wing's angle of attack will be low and the tail's angle of attack will be an even lower positive angle, zero or even negative. So you see that the lift off the tail changes as the wing's lift changes depending on the flight mode. So the tail's lift changes from positive to negative during a typical sport flight even for stable flight. So why doesn't the model constantly react to all this? Because the tail's lift is harmonized with the wing's lift such that the overall model acts as one unit to react to speed changes and trim changes in a predictable and consistent manner.

So just put the tail where it should be and trim as required.

Many model airplanes, not just free flight models, have tails that provide neutral or positive lift during level flight depending on speed. As soon as you put the CG behind the 25% mark you set up this mode where the tail has to lift from negatively to neutrally to positively in order to control the wing's pitching action at various flight speeds in level flight. This applies to trainers, pattern models and funfly designs.