Definitely haul him to shows whether or not you are actually going to show him that day. The best thing for him, desensitize him, and if you aren't showing, then you aren't putting the pressure on yourself, and him by extension by wanting him to be "perfect" in the ring. I took my Arabian to a few shows and just rode her or led her around the grounds, to let her get used to things, when I wasn't planning on showing, so there was no pressure for anything. After the initial "what is all this madness", she settled right down, and has been great. Really helped her do well when we trailered her across the country. I would maybe find a couple friends with horses that are planning on showing to go with, so he isn't alone, but his "buddy" isn't another horse that isn't showing, and will be standing next to him all day, or his neighbor who is always there, and that will help keep him from getting too attached. Good luck!