Sounds complicated Caddy, wrist for the first stroke, fingers for the 2nd...If the result of each technique yields double strokes that sound even in volume and are smooth, does it really matter that I bounced my doubles to get there? I just don't see how anything could be simpler and smoother than bouncing. I tried playing each stroke and it just doesn't flow for me that way. I'm talking tempos on the quicker side, beyond the zone of individual strokes. At that point, I naturally go to the bounce, that's not good?. Do you continue to stroke them out?
I come from the classical/rudimental world, where double strokes involve two strokes. When you bounce a stick, you are not applying any more inertia than the first stroke, and due to the laws of physics/transfer of energy/whatever, the second stroke will never sound as loud as the first stroke. It might sound close, especially from right above the drum, but not adding the momentum to that second stroke will make the double stroke sound uneven.
The "wrist-finger" technique isn't complicated at all. In fact, if you play with as relaxed a grip as possible while keeping your fingers on the stick at all times, once you break the 32nd notes at around 90-100 bpm barrier, your hands/wrist/fingers will do it automatically, without having to study and develop a special technique. Over the years, people have given it names, like the Gladstone technique or Push Pull or whatever, but it came from the natural movement of playing double *strokes* at a fast pace. You can play them fast enough to not be able to discern a double-stroke roll from an orchestral roll. Having to "switch over" from double strokes to bounced double strokes and back can also cause a hiccup in one's playing.
Of course, when you play in a band and everything's louder than everything else, and nobody in the audience can hear that you're playing accent notes on the high hat, it really doesn't matter. If you're playing a snare solo in front of a college jury, or tracking in a recording studio where your every stroke is critiqued and can be viewed in wave form, it makes all the difference in the world.
No disrespect intended. I'm just trying to keep the tradition alive. Having studied drumming/rudiments in depth, it's a shame to be out there watching drum line instructors teaching the snare line to bounce their doubles. Ugh...