I haven't played with the 710, but the Rukus does do this to me if I remember right. But, for me, it's unnatural to re-position the knife to get the tip of my thumb down in there. I'm spolied by the wheel stud....when my 975 opens, the knife is right where I want it position-wise. It's opened by the side fleshy part of the thumb. Ergonomically, we're all different as to how we carry, open, and hold our knives. Plus, once we get used to something, everything about it seems natural.
Then again...this space between the thumbstud and scales might all be subjective to my imgination.