Hi Simon,
There are. Richie Flores is one of the other known ones. Gio made the double popular and took it to the max; he got it from Changuito,who got it from who knows who. The technique has actually been around a while, have also heard it called the "flat roll" by some, but not many do it because it takes long to get down. My sound sample here is short, the rolls are doubles but short ones. I'm no Gio, but can spin clean doubles long as I like by now... maybe I'll add something with long winding rolls to my sound samples, just aimed for a quick taste here. Got to admit, I love rolls, the sustain of the drum. All kinds of rolls, bagels, too.