There’s an interesting thread on Facebook on this topic.
Most would consider cast handstand in a hollow / stretched position throughout as ideal. Nick Blanton mentioned this illustration from Championship Gymnastics.
It’s possible to do that technique. In fact it’s fairly easy on Parallel Bars as a swing handstand.
But I’m personally a very happy coach if the gymnast can lead with the heels (arch) to horizontal, then change the body position to hollow / stretched.
The ultimate would be perfectly straight through hips / trunk once leaving the rail. That’s difficult. The gymnast would likely be strong enough to do planche press without swing.
Gymnastics Coaching.com 
Rick, there are so many things (especially in WAG) where the “rules” are in direct contradiction to what makes sense mechanically (dismounts anyone?) that it seems a waste of time to even discuss it…..are we the only sport in the world where the umpires and NOT COACHES make the rules?
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