Just for a little perspective, back when I was an itty-bitty helper, I helped install five 20a fluorescent lighting circuits in a warehouse space. We dropped a 1" EMT to a 5-gang switch box and installed five switch loops, giving us a total of ten CCC's.
With the lights on (and yes, the circuits were loaded well within proper ratings), the conduit got rather warm rather quickly, so we added a second 1" and moved the five load wires over to it, so there would be fewer wires in each pipe.
Just kidding. :grin: Actually, we added a 3/4" EMT and moved two of the five switch loops over to it. Everything was cool then (pun very much intended.)
But, ten CCC's did get that first pipe quite warm.