I agree that performance is a mission driven objective. If the mission is ham radio communicating with someone through a repeater from the comfort of your shack that is a far different situation than the airborne navigation mission. Link margins and isolation from noise and interference take on a whole different meaning. If my life is on the line and dependant on objective expectations that I can tune in an ILS and fly the approach without loss of signal at the critical moment the only way I know how to do that is to know the theoretical link margins based on the specified performance compared with actual measurement of the ground based and aircraft based system components. The subjective “lick it and taste” approach is perfectly good enough for the ham radio environment but shouldnt become standard operating procedure for VOR and ILS in the airborne environment. I have always considered the gamma match approach to impedence matching to be a brute force approach due to the impact on the beam pattern and yes I do know how to tune and match an antenna even though I only have my trusty MFJ 259 that I mostly use to tune my ham radio equipment.