2.1 seconds, 25 frames (all unique), no sound
Persistence pays off! I finally was able to animate this the way I had envisioned it! If anyone's curious, here's my first (failed) attempt at a cat skip [link]
The problem I'd had with the last version was that I was moving the wrong legs. To do a full-body skip with a four-legged animal you can't alternate the legs like in a walk cycle (at least it didn't work when I did it). Also, a skip includes a bit of a jump (the cat is completely off the ground for a frame), something that I hadn't done last time.
I animated this with Pencil
(a free, open source program) because I was tired of Flash vectorizing my lines, and because I wanted to be able to play my animation back to check it (which I can't do so well when animating on paper). Pencil is kind of the best compromise of the two that I have right now. And it exports into a .swf, which is perfect for uploading.