Autorotate - I certainly bow down to your superior knowledge of taking photographs of helicopters, and keeping some sense of movement in the rotorblades was something I didn't consider in my rant!
"Reciprocal of the focal length of the lens" = fancy talk for "convert the number of the size of the lens (eg 28mm, 35mm, 50mm, 85mm, 200mm) into as close a fraction of a second (best to go higher than lower if you are concerned) as your camera will let you (eg 1/28th, 1/35th, 1/50th, 1/85th, 1/200th repectively")! This should give you a shutter speed that will eliminate obvious camera-shake when handholding the camera. Only works with 35mm cameras I think... And as with most rules there are often reasons when not to use it...
Apologies for all the brackets...