But, Humble, again it's not about how you CAN fly the plane, it's about how it was DESIGNED to fly.
You can fly a P-47D with 2500lbs of bombs and 10 rockets and use it as a dive bomber if you want. It wasn't a bomber. You can turn fight in a Ju87 (fun, for a brief period of time) but this is NOT a fighter.
The categories are based on the historical role of the craft in question, NOT how they are ultimately used/misused in AH.
P.S. The engines were upgraded, the nose faired over and filled with guns, but in general the airframe SHOULD be identical. Now imagine if the A-20G flew like the Boston III. That seems a lot more realistic than the Boston III flying like the A-20G, IMO. Chances are this is a bugged or inaccurate flight model from the first generation of craft ever modeled in the game, and if (when??) it's ever remodeled, these "features" may go bye-bye like the P-47s super turn fighter status did. Just food for thought.