Question on port matching

Rat Bastid said

All this talk of reversion, wet flow and all that is just that. The science says a step on the backside of the direction of flow will cause vortices and that is a flow killer and a power killer. If the step is in the direction of the flow, it will shear off and not develop vortices.

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It depends on what the engine is built to do and how it was built.
Turbulence along the edges is not neccessarily a bad thing.
In situations where it would improve fuel distribution and make for a better combustion. Now its back to droplet size, how well it mixed in the intake and stayed in mixed. Just as important how much heat, compression, etc vaporizes and distributes the fuel once the valve is closed.