*laugh* I assume some of the readership looked at the list, and thought all kinds of things.
A simple, shaking, rattling Feed Sack. :)
Is that a riot, or what? R shook the feed sack, with Romeo standing at a distance. His head popped up, and he wanted NOTHING to do with it. So I let him walk over to sniff it, which usually works. No-go. I had R walk away from us, rattling it, and we chased it. Then, I turned Mo around, and let the "shaking sack" chase us. I allowed Mo to rest, and the sniff the sack again. Success! He touched it with his nose, realized it wasn't going to harm him, and issue over.
We followed R's truck down the road - Flashy lights, blinkers, rough rocks bouncing around, no spooks. R turned back to home, and we "chased the truck" to the house. There, he honked a few times, with no Mo reaction. Finally, I handed him the bag. He shook the bag, honked the horn, and moved the truck around a little bit. No reaction.
Mo and I played silly spooks for probably 25 minutes, if not more. I explained to R what we were doing, why, and how. He was a good help, and a great sport, noticing that as soon as Mo would calm even a little, he'd "up the ante", increasing the spook intensity. Mo's an easy teach...