Interesting theory, although I have ne of my own. I think that despite what this games dashing options turn ou tto be, based on what I've seen and what the MK team has said and stressed about "both players being on equal ground and the defender having options to escape"
I can't possibly imagine seeing a more aggressive rush game in MK9 as oppose to UMK3's run button which made for a devastating rush game with little options for the defensive player to do much against. MK9 I do believe will be more "equal fotting" in terms of aggressive players vs defensive.
The run is easily far easier to cancel from then a dash.
I like and fully support this however and agree with the MK team's reasons here. They know UMK3 is a great game, but I think they also know an aggressive player in that game has the edge over the defensive player, this game they want to make it more balanced. Fine by me.