While I do not use tenting or physically split keyboards, I have been using ergonomic split keyboards for ~16 years. Not sure if that exactly fits the category you are looking at.

The specific keyboards have been the Microsoft natural ergonomic keyboard 4000, Microsoft Sculpt, and Logitech ERGO K860. I’ve been gaming on the PC since the early 90s and have been in IT and software development for ~26 years.

I have had no issues with carpal tunnel or RSI. While I obviously cannot say it was 100% due to the split keyboard design I believe it has likely helped to keep those issues at bay. Once you are used to a split keyboard design you can feel the pitch and stress on your wrists when using a standard keyboard. I have also always used the riser that rises the wrist end of the keyboard so you fingers are sort of “falling” down toward the keys.

I used that Microsoft 4000 keyboard for years, cleaned out the membrane on it 2 or 3 times before I had to replace the entire keyboard. Then was left hunting for something to replace it; I tried a lot of keyboards. In the end I’ve settled on the Logitech K860.