Why no plate R B4 cathode follower?

[FUCHSAUDIO]

In that circuit location the values (as they increase), will eventually start to close the circuit's bandwidth. The knee frequency gets lower and lower as the cap gets larger. I think the intensity of what these caps will do in gain stage vs a non-gain stage will be quite different. It might take larger values to actually hear or measure a difference in that circuit. This would also be affected by the source impedance of what's feeding that stage as well.