There are a lot of engineering principles involved with coolant flow and heat transfer. The various holes in the head gaskets are sized to allow a prescribed amount of coolant flow. The size of the coolant passages in the head/block are the size they are for at least a couple of different reasons.... 1- Manufacturing ease and core cleanout. 2- To control coolant flow.
This is why the article was written.... Wannabe vendors just can't decide on their own to change coolant flow without some sort of dynamic testing on a fully instrumented engine to measure the effects of any change. The vendor data should also be published so it can be verified.