What do the squares represent?

Your work is great, kudos!
What I like even more is that is 2020 fresh material; that's very good to see in PJ

Thanks for sharing the Ferrari presentation. 
 

Sadly no good tutorials.
But there is this GDC 2016 talk where Mark Ferrari explains a couple of ways he used to apply it. Starts around minute 49, though I recomend the whole thing. https://www.youtube.com/watch?v=aMcJ1Jvtef0

Do you have link to a good tutorial?

I wanted to try color cycling anim for a long time :)

And cool works! - especially cars

another silky smooth anim!!!