I agree with part of you statement as far
as bad idea for using 59 for in a customers house.
However back to basics it does depend on distance and frequency. HD will work on 59 with NO problems, but over a shorted distance than RG6.
As a matter of fact a lot of headends only use 59 to transport HD signals from a QAM modulator to optical transmitters. We have transmitters that wont except a 56 wire because the center conductor is to big, so you have to use 59.
However back to basics it does depend on distance and frequency. HD will work on 59 with NO problems, but over a shorted distance than RG6.
As a matter of fact a lot of headends only use 59 to transport HD signals from a QAM modulator to optical transmitters. We have transmitters that wont except a 56 wire because the center conductor is to big, so you have to use 59.