Thany you guys for your answers to the question raised.

I agree that actual head flow numbers don't necessarily mean higher output.
A large cross sectional area will show better flow numbers, and not make
the power output it could.

However, having some guy say they "look good" is a bit of a stretch - even for a
very experienced head porter. I can change the valve seat angles, and change the
head flow by 5 cfm ( you can't and wouldn't know unless it was flow bench tested )
I can also remove 1mm of material (on the wrong side of a CVH port) and reduce the flow by more than 5 cfm - again you cannot look at the port and see these differences.
The backside shape of the valve also has a large impact on the flow - this must be matched with a specific short side radius and valve seat angles - or the resulting flow will be lower than expected.
This work cannot be done without a tool to measure the changes.

A good scientific head porter knows (or should) the importance of port CSA, port velocity,
etc..

A flow test also does not guarantee that the head porter knows what he is doing. It is just a tool to measure changes being made to port shape, valve seat angles, and port cross sectional areas.

One has to have a measuring device of some type - the engine has a dyno to measure power output, the car has a racetrack lap time to measure performance.