I have no idea what happened to version 6; either it got overwritten or (more likely) my naming conventions suck and I accidentally skipped a number. Whoops. I'll keep it labelled thus for now until I figure out what happened. Preferably when I'm not so tired.
I was getting very flustered by this point so I scurried off and found yet another reference video. This one, I must admit, is pretty brilliant.
I cut it from what I think was a student film (11 minutes long!), and unfortunately they put some sort of peculiar stagger effect on it, so it kind of jars the image. If you spend long enough scrubbing through it you can sort of get a feel for the overall motion, though.
Immediately it's apparent where I was going wrong last time - you can see that the shuttlecock hits the ground and flips forward before landing on the corner, which then knocks the cork towards the ground, where it knocks the shaft back again and so on. Very, very, VERY similar to the motion in the previous video, so I was able to put two and two together and kind of understand the overall mechanics of the thing. Subsequently:
Now that's better
The new reference video clearly helped, I think. It's not perfect by any stretch of the imagination but I think it's looking a lot better.
I think it possibly bounces a little too far forward (though I suppose it depends on the force of the launch) and perhaps it could stand to bounce a little higher?
The other thing I notice is that maybe it rotates a little too much. Currently, as it flies through the air, one of the corners brushes the ground but it keeps rotating until the other corner hits the floor, then it starts bouncing - I could have it bounce off the first corner and it might look a little better. If that makes sense.
After it bounces off the corner and lands on the cork, it kind of skids along the ground before rotating back onto the feathers - I think I probably need to have it bounce a little more instead of skid.
But, other than that, I'm feeling a little happier. I'm concerned with how simple it is... it just sort of bounces in a straight line. I feel like I should fancy it up a bit and have it bounce or rotate in a slightly different direction but I don't know. Maybe that's not important. I'll try to worry about that later.