We warmed up in the short court with two other riders, the first time I've ridden him with anyone else in the ring. He was tense and hollow-backed. Despite his tension, I still rode in and around other horses who were spooking and cantering, and I was able to use the whole ring. So even though he was a bit of a mess, he showed me that he can handle a warm up ring.
At about the 30 second mark, Jackie's horse gives a big spook at A, and it takes Izzy a few seconds to see what is going on. Once he sees Dempsey being naughty, he starts thinking about getting the heck out of Dodge. Here's the video:
A little bit later, one of the horses in the barn gave a nice snort as we were trotting by, and Izzy did an awesome reining rollback.
I am not sure what he was fussing at in these next photos, but in all likelihood it had something to do with softening (or not) to the outside rein.