Confused about raid 0 stripe size

If you are this concerned about HDD performance, why noy just buy a SSD?

A decent size SSD, ( I have two 128 GBs in a raid  0 ) and then use your platter drives for storage.

If you used 1 SSD and raid 0 your two T-byte drives, you’ll have a great performer.

Sorry this doesn’t answer your question but perhaps will make you satisfied with a good performance setup.

Iommi