Sometimes, a little extra exhaust can help cylinder fill. But this and many other factors of cylinder filling and optimum efficiency in a given parameter (engine/cam rpm range) can be a huge trial and error experimentation. There are so many things to look at and consider when that cam starts turning.

On single pattern vs. the use of a split duration cam, I have found best results with a split pattern and stock heads. Why? Because the exhaust could use that help? I think so. On ported heads, I haven’t seen any real advantage with a split pattern and the single pattern ran quite nice.
No 1/4 slips. Just basic street builds.
Still playing around with cams in the various engines.

While this thought/idea may not play out accurate, perhaps a computer sym like Desk Top Dyno could be helpful in at least show what could happen with a different cam. If anything, it could be a helpful tool in showing what is possible/probable.

Have there not been published reports on flow balances between the ports and suggested cam specs for such balance