port matching the intake manifold?

I recall in the "old days" early 80's when folks ask about using a Holley intake which has small size 318 ports on a 340 motor the tech guys at Hot Rod and Car Craft said its fine. In fact they said its better to have a smaller intake manifold port than the head. Something about being able to run a big cam and the smaller ports would help stop the air from coming out of the cylinder at slow rpm's so you can run a bigger cam. Yes I leave it alone.