If one could swipe through the center without inserting a space, it would be incredible instead of perhaps only great... There was a PalmOS 5 keyboard like this named myKbd(1) based on some IBM research(2) which was quite fast to use. the atomik layout was quite quick to use.

(1): https://palmdb.net/app/mykbd

(2): https://doi.org/10.1207/S15327051HCI172&3_4 https://blakewatson.com/uploads/2023/07/Performance_Optimiza...