Svoynick - That famous clip was a JFK ground controller. Don't know if it is a sticky LiveATC link here, but it is on YouTube:
And Salarcot, it all depends upon the location of the feed antenna in relation to the ATC ground stations and the aircraft. An aircraft on approach is still airborne, relatively close and will come in pretty strong, but other aircraft that are closer to the ground station or have a better path will hear ground over the stuck mic. You really have no way of knowing where the ATC ground stations for approach and departure are without research, but often they are NOT located at the airfield, often many miles away, so the effect of a stuck mic on overall communications is fairly unpredictable. These transmission are AM, so unlike FM there is no "capture effect" and almost all signals can be heard by anybody even if it is just a weak heterodyne (squeal or tone) in the background under the stronger signals. If the aircraft were 25kc off the heterodyne would be inaudibly high even if the audio sections of the receiver and feed chain could pass it to your ears (which would also not hear it unless you are a dog or a bat), but most receivers and scanners would not pick it up at all unless very close/strong, and if off by say a couple kc you would hear the heterodyne.