Jesus Dave you have been Crazy busy!
I remember these when they somehow made it on to a TV show. Maybe Idiots Den years ago I dunno. Probably been copied since then. All my jackets generate enough flappy wind with the cuff zips left open though.
My summer jacket has big vents at the back too, which when open promote superior airflow, fnerr! (Superior to what I don't know. Maybe those bits in the ocean where the tall ships used to get stuck for days/weeks. Did you know citrus fruit was an old wives tail for avoiding/curing scurvy for years but nobody tried it scientifically until the guy who Cook listened to. Apparently 50% seamen dying at sea for 200 years was just fine)
