MechE and recovered car nut here.
If it specifies premium - use it.
Your Acura is probably smart enough to retard timing in response to regular fuel, however you don't want it to.
1.) the engine won't be running optimally, as designed. retarded timing will result in less of a complete burn and less torque.
2.) there is no such thing as a 'regular fuel sensor' in a car. when you add regular to a car designed for premium, it will probably result in knocking and pinging. This is detonation and will kill your motor over time. However, your car has a knock sensor that's extremely fast to react. When knock is detected, it will immediately retard timing in response. It's so fast you probably won't hear any knocking. The problem is, there is no way for the engine to know that you haven't refilled it with premium. So it constantly advances the timing, listens for knock, then retards it again. It will be stuck in that cycle until you put premium back in.
As an MMM following, this should be a non issue, anyway. In my case, gas costs are about 1% of my gross income. If I had to use premium, that's just noise.