Probably, but i think it more has to do with how it fits your head, and how much you bend your neck...
I've got a Bell Meteor (II i think), and if i slide it back, so it's not covering much of my forehead, it starts to touch my back, but if i wear it in a more 'natural' helmet position, it sits up a bit more....
That's my experience! If you can drop your bars more, to get your front end lower, you'll have to look up more, and that'll get it closer to your back....but could very well compromise your power output.
I like the newer designs that have a much shorter tail, and are still pretty aero if you put your head down (like you see Dave Z does.)