As a native English speaker, I also felt like I had to work harder to read the bionic text.

I am first grade teacher and have taught many children to read. Bionic's principles and algorithm do not match what I understand about the science of reading. This just holds the first part of a word, regardless of what the letters are. I would want an algorithm that is smarter than that (and I certainly wouldn't use bionic in the classroom, regardless!).