Lets clear this up for everyone, VELOCITY is SPEED, VORTICIES/VORTEXES are turbulence produced when SEPERATION OF AIR TAKES PLACE FROM THE PORT WALLS/FLOOR/ROOF BOTH SSR & LSR, VALVE SEAT&THROAT, VALVE HEAD as well as the guide area.
COMP, if you have an engine that is suddenly loaded gas or diesel, you WANT a port adequately sized to be able to recover easily to keep going. I believe air speeds are of higher important along with rotating weight especially in the realm of creating good throttle response.Technically we should be saying pounds of air into the cylinder but the only way we get that either is if the air charge is flowing properly both in least frictional loss and port routing.
IMO, as long as people engineer the drafting table designs, these flat runner layouts will not go far too fast. I believe port position is holding diesel intake & exhaust flows back from opimization as far as one part of the higher rpms picture. I see you are keeping Clay Smith's legend going, love it!
Swirl is induced naturally with two valve heads not matter what. 24 valve engines will produce tumble from the valve unless the port is designed to promote swirl coming out of the valve bowl. As our squish action, piston movment toward and away from TDC, the bowl should create both swirl and tumble at some point. As you have stated, swirl slows flow down when coming out of the head into our chamber, reason is its a long distance to travel, entailing a longer cam lobe duration may help the engine out.