We have a fairly informal process at our gym. After states, it's all up training and they move girls who are ready at the end of June. They do additional (informal) evaluations over the summer and move up any remaining girls who've attained the requisite skills.
There are plusses and minuses to any evaluation process - formal or informal. I kind of like the flexibility afforded by an informal process, and if you trust your coaches they really should know what's best. However, I feel a little bad for some of the gymnasts and parents, who just really want to know what does it take to move up. For level 5 - you've got to have the kip by the end of the summer. For level 6 - backwalkover on beam and flyaway. Those tests are pretty straightforward.
Problem is there are so many subjective factors that prohibit a quick checklist - is there room for gymnasts to move up? Is a gymnast mature enough for longer practice hours? What if a gymnast has the basic skills, but tended to fold in meet situations? Some of our parents are secretly crossing their fingers that kids won't move up because they can't afford the additional cost.
Sorry for rambling. My daughter was one of the early movers this year, but there are a number of others anxiously hoping to follow in a couple weeks. That brings a little stress to the gym.