Concatenated (JBOD) disk set for optimized media

Heres the issue:
Playback of XAVC-HS UHD gets a little laggy on FCPx even on my M2 Max.
So I wanted to created optimized media for the whole 30 min timeline.
On my SSD there was not enough space - so I rendered to a HDD.
It takes slightly less than 3TB and runs quite fast BUT playback constantly stops as the hard disk goes to sleep -
even when I set "put disks to sleep" to "never" in system preferences.
Now I would like to use my SSDs: I have two 1TB and one 2TB.
It doesnt seem possible to split the optimized media to multiple drives easily.
(I could use a smart bin for used media and then figure out how many of those files into one drive and then switch the media folder in settings, but that is a little complicated).
So I thought of combining two or three SSDs to a single drive using JBOD in Disk utilitys - so I have a four TB SSD I can use. Did anyone try this before? Does it run stable?
As its only the optimized media I wouldnt care too much if media gets lost accidentally, I just need a little more performance for a few days.

support.apple.com/en-gb/guide/disk-utility/dskua23150fd/mac