To me, its no coincidence that some of Tannehills best and prettiest throws have been to Kenny. Stills' ability to stretch the field and get open deep has not only given Ryan an outlet, its helped him develop an aspect of his game that got few chances to arise in games before Kenny arrived.
Yes, they have chemistry. But the better news for Miami fans is that the chemistry they have is opening up the game for Tannehill and making him a better player.