Only thing I don't understand is:
#Click calculate, then add .json to coins at the begining of the address after you click calculate!!!
I have two rigs, one with Nvoc 19 and other with centos7 (no switch there) and I may be interested in adding the switch once I fully understand how it works.
When you set your cards, hash rate, profit, difficulty ,... on whattomine.com and click calculate it creates a link for your settings, then you should add .json to make it readable by the script.
created link is some thing like this :
https://whattomine.com/coins?utf8=✓&adapt_q_280x .....
you make it readable for script by changing coins to coins.json like this
https://whattomine.com/coins.json?utf8=✓&adapt_q_280x ...