I agree with the above but would like to add.... while in "recovery":
-Longe him before you get on.
-Use a mounting block ALWAYS.
-Don't plop down when mounting..
-Ride in a half seat or two point, staying off his back.
-Get a neck stretcher and ride in it once or twice a week. (Warm up with out one first!) Low, stretchy, large circles.
-Flex and stretch him before you ride.