10 tries? I would say this is almost like the kip in the difficulty for gymnasts, even very talented ones. I've seen girls get a lot of hard skills quickly on floor, vault, and beam. But I don't think I've ever seen a girl doing free hip to handstand in any close to 10 tries. That's less an average optional bar rotation. Learning a free hip handstand "fast" would be to me, oh, about 3 months or so. That to me would be fast. I know plenty of L10s, even good at bars L10s, who took longer than that. Were doing it for 6 months, a year before they were even doing spotted handstand. And then of course, with optional rules, they need to go handstand to handstand even in L8 not to get amplitude deductions. Even trickier. Before many L8s were doing A cast to free hip handstand.
We have to keep in mind they don't have much of a reference with this skill at that point. Typically this is the first skill to a clear support in the US (we tend to teach it before or concurrently to giants). With many skills in gymnastics that a kid could be doing at this level (i.e. BHS on beam) they have a reference - they do BHS on floor. Double full? By that point they have done a lot of tumbling and twisting and they may be able to understand the mechanics of this pretty quickly if the right "gymnastics properties" align. So they can get it very fast if they are not afraid and have the proper strength and flexibility. Here we are trying to get a kid to do something they have never really done at all. We're at ground zero. So like the kip, we are going to have to do a lot of things to get them doing every part of the skill correctly - the drop, the shoot, the shift, keeping straight arms/not collapsing, not leading with the belly. Even after most kids are able to get themselves up to handstand, it's just a start, because most often there is a shaping problem that needs to be worked on and the skill is still not very powerful. Things like back extension rolls are helpful but it is not the same as swinging around a bar. I was able to do a back extension roll pretty much the day whenever someone showed me, maybe a couple months after I started in gymnastics. Free hip handstand, I would say from the introduction of the free hip, probably three months on strap bar and six months for no straps to get the handstand without spot.
If both sides keep working and do the appropriate drills for shaping and timing, then it pays off. Like most bar skills, progress seems slow. Usually they aren't doing it, then things start clicking, and suddenly they're doing it by themselves, and 3 months after that everyone's forgotten that at one point this one was the kid always crying about it or falling over the wrong way or never shooting at the right time without a spot.
. Instead of timing a toe hand, I just use it for the girls to shift. I yell now when they need to shift to hand, and they do it about 3 times, and then count in their head, and then they usually get it! 
