the rpm does drop when you steer, or hit the brake because of the load on the engine. the alt puts out significantly less voltage the less rpm you have, this is normal too. the sense wire is what tells it its too low and to increase output, almost all other newer cars have them from the factory, i dont know why the bonnies dont have them but mine has done that forever. it never stalls out if yours doesnt stall i wouldnt worry about it.

well just in case i will be checking the car for a parasitic drain to see if that'* the culprit