Here’s some hair on a plane, rotated with a bone.
Hair Jitter.zip (1.1 MB)
Suffice to say, this looks a tad conspicuous on a character that isn’t being electrocuted. The Curl Hair Curves modifier appears to be the culptrit in this instance, however I have a more complex scene in which Interpolate Hair Curves and Frizz Hair Curves produce the same effect.
Basic user error, or glaring bug?
Thanks for any help,
(c:
Hi,
So what kind of a result are you trying to achieve? I don’t get it.
Just for the hair to not jump around spasmodically while the plane rotates (I’ve changed the title in case that wasn’t clear).
Try to disable Gravity in Scene settings and check if it’s helped you
Interesting suggestion, but alas, it didn’t help.
IDK whether it’s gonna help you or not, but I’ve just found this one 10-year-old post which describes the similar problem (at least how I understand it):
Thanks for the suggestion, however that fix seems to apply to hair particles (which I’m not having the jittering issue with), whereas I’m using the new hair system and accompanying hair assets.
No problem
I’ve been surfing around the internet for your problem and came across a few similar questions, which, unfortunately, haven’t been solved 
Not to worry, I appreciate the effort. Unless someone else chimes in I’ll assume it’s a bug and submit a report.
Came. here with the same issue. Very frustrating… Thanks Chris for making that demonstration
For me the issue does seem to be with the “interpolated children”. But I havent found any kind of plausible workaround
Seems like it’s really a bug:
It’s strange, this tutorial uses the same technique and seems to animate just fine (see 11:00)
I cant figure out how it seemed to work ok for this person…
Meanwhile my own renders come out looking like this
So … I can reproduce from scratch the bug you have. And I found a weird behavior about it.
If I use multiple geometry nodes like in your example, I get the wobbling effect.
But if I chain the node group in a single geometry node, I get no wobbling effect.
Actually, I can reproduce the wobbling doing it in a single geometry node If I put the Deform Curves on Surface before all the other node groups.
Your example works as you would expect if you change the geometry nodes order to have the Surface deform last:
Thanks for the replies. I submitted this as a bug report last night, but apparently this is considered “expected behaviour” when Surface Deform is at the top of the modifier stack (as @MadeWithFeet discovered), and the report was closed.
However, this does nothing to alleviate the problem in my main scene file. In fact it only makes matters worse!
Here’s the Surface Deform modifier at top of stack (technically one down, but the results are the same):
Surface Deform at bottom of stack:
So I’ve reopened the issue, and now I guess I’ll have to try and reduce the original file to something demonstrable without losing the issue at hand. That should keep me busy for a while…
I had actually been using the old particle/hair system, not the new geometry node based hair assets. This node-based hair system was the workaround I needed … no more jittering here-- in my case this worked, thank you!
