You know how some people complain about dashing vs walking in Kid icarus: Uprising? or having a "run button" in SM3DL? Those wouldn't be issues if the CP had a much greater travel distance, which would allow better "pressure based" detection of speed. Yeah, the CP can do that, but nowhere near as extensively or effectively as a typical analog stick. Otherwise, you wouldn't need "hard"/"double" tapping of the circle pad or holding run button to dash.