The diamond braid was not done to train Gem's mane.. it already stays down on that side. I thought it looked really cool on a website I saw, so I decided, since he has the length, to do it.
Vega's mane, after putting a sleezy hood on it, has been doing really well. I figure i'll braid it in a few days to really help it stay down.
The diamond braid is really easy to do too. If anyone wants to know, let me know :)