Maybe just coincidence, but I have the swipe select tweak on my JBed iPad Air, and as much as I like the features, I have turned it off because the tweak seems to be messing up my regular typing on the keyboard, many more errors beyond "typos" like 4 out of 5 letters of a 5 letter word disappearing after I thought I typed them, etc.
I do not know exactly how, but maybe because swipe select tweak—as well as the very similar new iOS 9 keyboard gestures—does some odd stuff with how the individual keyboard keys are touched, or the spaces in between the keys become active with swipe select, or the keyboard keys' touch target space changed size or acts odd with new gestures.
I am not sure as I am not an app developer, but there could be some serious keyboard typing usability issues with these new gestures that turn the keyboard space into something similar to a trackpad, which might be why Apple added in the very deliberate swiping from the bezel.