I don't see why you can't sideslip a swept 75/76/73 gently enough to see how it works, and keeping the Vmin or (stall) margin high enough and within weights, I can't see how it can cause problems (anhyedral excepted). ?
How about taking the chance of blanking some of the airflow into the jet engines at low altitude/airspeed ?? Cough ...spit ....sputter Oh my look at that EGT !