No one actually knows how to lculate what speaker cable they need

Mr. Dill
This banana plug is as good as it gets. A friend who was a QA at a large hi-tech firm checked the subject and ended up with those over all others.
The tip is making a way better contact (felxibility and surface ares), than other methodes. It also last longer and can connect directly to an 8 AWG wire. Thicker than most others would. They can get wires only as thick as 12 AWG.

Regarding the cable, it might be some better or more expensive stuff out there. However, the calculations and the results, show no complains.
Why pay more? much more?
What is the market price for a 2.5m (8') long, 0 AWG speaker's cables set?
The last I've hurd of, made by a respected brand (!) was $32,000.-
for a 4 AWG.
They have on the TOTL a 0 AWG too. I assume it is even more expensive. I can get it done and shipped for way less, including an accurate calculation for the best required cable for the system.
Expensive is not a better quality. On a market, that two items will deliver the same, the cheaper will prevail.

Regardles of experience, NONE came out with the answer:
How to calculate a speaker's cable, or even a clue of what cable is needed. I understand it is hard to admit such a thing, at a time claiming of so much experience.
The other ideas were much of let's give it a try and hear if we like it.
Not a sucssesive way to get it right on the first trial. If having experience like that count's I'm out. But I think, it doesn't!
What is a very experienced member? 10 years, 20 years, 30 years...of experience?  I've 45 years. I'm in this hobby since i was 15. 
I orgenized 6 audio seminars, demos, lectures, on the 3rd, Mr. Yair Tamam, founder of Magico speakers gave a speach on speakers...and the list goes on and on.
Experience alone, wont help. Some education in electronics, working with the top Hi-Tech firms, using the ears and mostly what's between them - is more important. The problem (understanding the way how to calculate the speaker's cable by the equipment it connects) is solved. Now it is only for you and other members to accept. Thanks.

Just seen this add. on this site:
http://www.jpslabs.com/speakercable.shtml
For jps cables.
Not a word on any technical data: resistance, for what equipment they are good for...They do talk about a lot of power (Watts) or current (Amp’s) and a shield for speaker cables: What is that good for, at a time the Amp. output resistance is less than 0.016 ohms (FD=500). This is more like a short circuit. Any one who knows a little in electronics, can tell you it won’t pick any noise. And the output signal is relativly large.
They look awsem. I can give them that. Put them a silk tie or a dress and they are ready for a graduation party. Is it important to look that good or is it important to fit the system or produce a btter sound?
Somthing must justify the price...So lets do them look good.

b4icu, would you like to show us the naked termination going from the 0 AWG cable to the spade or banana connector? I would like to see how you did that. Thanks! 

Sorry, I have no picture of that taken.
I'll try to explain.
The ideais to use a short 8 AWG (the thickest wire that can fit into the banana plug) that is going between the banana plug and the 0 AWG cable.
As I said in one of my posts, an 0 AWG can not be soldered. It takes to long till the tin melts. By the time it does, the plastick sleve is damaged and a significant part of the cable's adge is subjected to oxidization.
I use a cable shoe to fit (DIN 70 size) and crimp it with a 0 AWG crimping tool.
https://www.ebay.com/itm/DROF-Mechanical-crimping-tool-for-10-to-2-0-AWG-6-to-50-mm-Made-of-Steel/16...

The 0 AWG is kind of difficult to work with. every step that would be eassy with an ordinary wire (up to 12 AWG) is getting bulky.

I do not use spades. They are not good for contact (it gets lose in time) and every here and there it need's to be fasten. An endless maintenance.

If you are into make one for yoursrlf, I may offer you that service.