Flow has nothing or little to do with it. It is about making restriction of flow as low as possible/practical.
Long hose is restrictive. Even with supercharging, restriction to flow is a part of the equation.
Often people just build what looks right to them. I am no exception.
On a Pantera, the best source of unrestricted cold air is from the roof area.
The real reality is that there is no noticeable difference until you go to Bonniville and attempt to set new records, not on the Freeway.
If you are driving around in Death Valley in the middle of the summer, don't expect to find any free horsepower there. Infact, you are likely to be loosing 30 to 40, aka, "bad air".