A technician, in a hurry to restore service, may not recognize the standing waves barely evident in graph 2 and lose valuable time. The information that the resistive test points allow is valuable and has its place. Life was good. These uneven losses often cause P-V failure when sweeping through line extenders. Passive counts between amplifiers increased.
Taps are everywhere now.
The major concern with passive loss is the uneven attenuation across the bandwidth. Attenuation increases as the frequency increases, but not at a predictable rate, as with cable. A graph of any manufacturer's tap loss will show a crook or a knee between 550 MHz and 750 MHz. Passive loss inequalities are responsible for the roll off above 550 MHz. The impact of this is apparent when you consider the design of an equalizer.