When you have multiple restrictive blocks in parallel, you will not have bottle neck in the system. I dont know why ppl even consider series in this case.
Ppl really overthink this. You can have multiple loops with common coolant and heat exchange (ie. 1 pump for each C1, one giant rad - NOT in series....)
I never said the full series solution is the best, just that people were overstating the amount of flow you need to keep the coolant at acceptable temperatures. 2l/min isn't much.
Having a large series string with a couple pumps does have other benefits as well in terms of reliability if there's a pump failure, and possibly easier routing of tubing.