Switching can be a pain in the butt, but it depends on the circumstances.
You should take it on a case by case basis and aim for easiest option.
So most of the time you switching back and forth is more trouble than it’s worth – but there’s always a situation where that would actually be the easiest thing to do as well.
For the kick – I stayed in IK (to the root), but if he was jumping off a diving board or something, then I would probably switch to either FK or IK to the hips where appropriate. (most likely the latter). But it depends on how many frames that is. It might be easier just to control in precisely for a short time rather than deal with switching difficulties.
I hope that makes sense – I feel like I said the same thing in 7 different ways haha.
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