I don't think he's lost a step, but i think he is being more conscious about not running as much or taking hits while running. The irony is that the hardest hits he takes and the nagging injuries seem to be when he gets nailed in the pocket or behind the line of scrimmage.
My other Josh observation, and i haven't mentioned it on this board yet, is that JA17 looks thinner. He's still a big guy but they used to say he was 6'5" 245,,, He looks more like 220 now at best. Maybe I'm wrong. I noticed it over the summer on his golfing pictures and then in recent interviews. Hope that doesn't affect his durability. He's probably eating more healthy and more nutrition conscious.. who knows.