I can completely turn off any 1 of the 3 PSU's while the rig is mining and it will not skip a beat and continue mining shifting the load to the other psu's

So, only one power cable for the psu in the middle ? or all? for what aim in the end ?
No, you will overload the cable if all those GPU's end up trying to draw power through a single cable.
example on my 1200watt psu rigs, 6 x 1080ti's
3 cables to 3 x GPU's from PSU 1
3 cables to PSU 2 from PSU 1
3 cables to 3 x GPU's from PSU 3
3 cables to PSU 2 from PSU 3
So i have 6 cables running from the spare PSU daisy chaining the 2 other PSU's
I ordered this style breakout board from aliexpress for $1.90ea, i bought 50 of them at the time

