I come to keyboards from a slightly different background. I am missing a couple of fingers, on my left hand two fingers and one thumb can reach keys, on my right hand three fingers and a thumb can. I never learned "home-row" typing or any other fixed method, but I can comfortably touch type above 60 words per minute. This is a point of pride for me.

I resisted the idea of split keyboards for quite a while because my right hand, with its greater dexterity, was responsible for more than half of my typing efforts. However, I got one last year (Kinesis gaming, tented, wrist rests, MX Blues). It actually helped me retrain my typing to be more evenly distributed between my two hands.

Later, when I was transcribing interviews for my book, I was typing for hours at 40-50 words per minute. I started out doing this on my laptop, but I got substantial hand pain from doing so. I started only transcribing in my dorm room, where I had access to the split keyboard, and it fixed everything. One day I typed more than 9,000 words without pain.

In summary, the benefits of ergonomic/split keyboards are real.