Bypassing capacitor caps , and caps in General

With regards to tube amps etc ...

Power Supply Filter Caps and Decoupling Caps:
Do you guys agree with the train of thought where high capcitance electrolytics are "slow" to respond to sudden quick music signals which demand a "quick" instantaneous supply of power to the tubes? I have read that bypassing with a smaller value film cap, either a 0.1 uF or a 1.0 uF + 0.01 uF can help "speed" things up. I have heard that this theory or practice is from the '80's (maybe they didn't have such good caps then) and that nowadays, it is preferrable to use good quality electrolytics (such as Black Gates) rather than just any old large cap.
Or does this apply to decoupling caps only? Decoupling caps are local power supply caps, yeah? How do these differ from large electrolytic filter caps, function wise? Don't they both do the same thing, to supply power to the tubes? Why the need of a local power supply? Seems like my TRL amp doesn't use decupling caps, but several large computer-grade electrolytics. These I believe are filter caps, rather than decoupling caps.

Signal Caps and Coupling Caps:
Similarly, bypassing is used in coupling caps too. I have read of pros and cons, and am not sure if it is worth trying. In short, I have been told that large value coupling caps have better bass, likewise with large speaker drivers. However, like the large speaker driver, it has poor high frequency. Similarly with large decoupling caps, they will have poor high frequency - hence the small bypass across it - essentially, adding a tweeter. Or you could add two bypasses to achieve a mid and a tweeter.

Black Gate Electrolytics:
Ok - these are mega expensive electrolytics and are known worldwide by enthusiasts as the best electrolytic out there. Audio Note Kondo makes very pricey gear - they don't use these for their electrolytics in the power supply. Why is that? I own a M7 phono stage and it uses what seems to me to be standard Nippon Chemi-Con caps - not Black Gates. How much improvement will Black Gates offer in comparison to the Nippon Chemi-Con caps if I was to replace these in the M7. Should I? I believe the Nippon Chemi-Con function as filter caps and are positioned around the mains input transformer.

V-Cap TFTF:
I have read too many astronomical improvements when other caps are replaces with these. I'm going to bring up Audio Note Kondo again. Has anyone replaced AN caps with these and got better results? Or even bypassing the AN caps with a V-cap. Should the V-cap be so excellent, it's a shame Kondo do not use them. Maybe they want to keep their gear 100% Japanese.

Comments and opinions appreciated.

Regards
David