I accept completely what you are saying. I understand the mechanisms that are at work here however the tests I have done lead me to believe the internal capacitance within the factors are what is causing the , admitedly small, treble loss.
Using a George L's cable from my loop box to first the PF, then another to the TF and then back to the loop box with another. Thats six Georgle L's connectors and approx 2foot of cable. I can detect a very small loss of high treble, sparkle if you will, when the loop is switched in and out and both pedals bypassed. Switching the PF to dsp bypass I get slightly more treble loss and a drop in volume.
Now the remainder of my board consists of 7 pedals.
Turbo Tuner St-200, 7" George L cable to:-
Menatone Blue Collar, 2" George L cable to:-
Menatone TBIAC, 2½" George L cable to:-
XOtic BB, solid connector to
Xotic RC, 2" George L cable to:-
MXR EVH Phase 90, solid connector to
Rothwell Love Squeeze
When these are connected to the loop with two additional George L 7" cables (at the start and the end) I can detect no treble loss whatever. A 5m George L cable in the loop alone produces no loss. Neither does the recently acquired 5m Providence S102, though the Lava Soar cable does lose an insignificant amount.