1. I am not a fan of the wall in general.
2. I have called out painting it as dumb.
3. your/the tweet argument doesn't make sense:
A) The temp is still going to go up, even if the side facing mexico isn't painted black. its all one big column, the heat will transfer from one side to the other without much additional heat loss.
B) If the idea is to burn someone as they are climbing, which is a dumb idea imo, they still have to climb down the US side, if you believed only the black painted bits get hot. a theoretically crippled illegal would still be a win for these people, even if they are crippled on our side of the wall. much easier for border patrol to find and collect.