There are a few threads on here about this. I think the conventional wisdom is no, because the cross bars are too flexible. I bit the bullet and installed a FrontRunner roof rack earlier this year.
Since first reading this thread, I’ve been on the fence about purchasing the Pedal Commander. I finally pulled the trigger, and install the PC27 BT yesterday on my 2016. My first impression is this thing kicks butt! I regret not doing it sooner.