I'm going to throw out a little speculating here. There is nothing scientific behind this. My speculation is, if you put a gigafoil with keces into your ethernet chain and experience a dramatic level of improvement, my speculation is there was a lot of noise and issues on your ethernet system in hole.
If all you do is utilize the Gigafoil with keces power supply in this instance, you have done a lot to clean up the signal, but have done little to address other underlying issues. Adding Keces PS to the router and modem as well as utilizing a audio quality switch will bring further improvements. IMO.
I talk on the phone and chat with Ed a lot. I believe my understanding of our conversations is that he keeps much of his music on his Aurender and passes it via Ethernet to his Brinkman DAC. Even in such a simple signal path, the Brinkmann to the DAC via his switch and gigafoil, he finds the sound improved by having a linear power supply on the router and modem which you would not think is in the signal path. I believe the router is still ultimately assigning the addresses so is involved in the process. I also believe Adrian with the Linear Solution was leading me to understand there is still distortion and noise from the modem and router that are injected into the entire ethernet signal and cleaning up the power supplies on those devices keeps their influence on the entire ethernet chained to a minimum.
In summation if you were to address all of those devices with better power and cabling you would find the Gigafoil to have much less influence on its own.
As a second summation, if you just use the Gigafoil and don't clean up the rest of the signal, you are loose some performance. Not a lot as the changes will be smaller, but you are losing some.
