“Hot air rising” is really not the best way to describe the full effect of the ridge vent pulling air through the soffits, IMO.
The concept is much like an airplane wing…where the air blowing over it creates a negative pressure that lifts the plane…the wind blowing over a ridge vent also creates a negative pressure which pulls the air from the attic through the ridge vent, with that air being replaced through the soffit vent.
When there is a gable vent or some other source closer to the ridge vent, the negative pressure will draw air into the attic through that source which is closest to the ridge vent.
In my attic, the warm/heated air rises to replace the hot air that was sucked out by the power fans. After it runs awhile it has warm air rising to a hotter area as it gets sucked out.
The ridge vents have very little effect on anything while the fans are running.
If the ridge vents “ruined” my setup then it would stay hot at the standing level and that is not at all true.
The entire attic (top to bottom and left to right) is actually very much cooler than with only soffit/ridge venting.
On a warm day, a little testing with a smoke pencil might go a long way in resolving these arguments, most of which seem to based on theory. I’ve seen arguments one way or another from some pretty credible sources (Certainteed Shingle Applicator’s manual, which I like a lot) but I never see any studies cited. I’d be inclined to believe Building Science Corp. if they have a good article.
The guys from Air Vent also said that all roofs are not candidates for ridge venting but emphasized that those that do have it, venting should not be mixed unless attic space is separated (blocked off) due to different heights, shapes etc… It’s about finding the right balance for your attic. By the way air vent used to be a part of Certainteed