Thank you to everyone for your comments, I really appreciate it.
I'll see if I can't write something to send in to the MHW, they talk about the ultimate gelding, I think he's it! A few years ago our club newsletter did a series of articles where people wrote about the "Greatest Horse Ever" and I wrote about Prancer.
Once, years after we were showing Prancer regularly, we took him to a show for costume for my youngest brother to show. They were putting on a Youth Showmanship clinic and we volunteered Prancer. He had a beginner showing him, but when he looked up and down the aisle you could see him realize that this was a showmanship class ... he carefully set his feet.
I've been very lucky to show a lot of truly great geldings over the years, but Prancer was the first, and because of that, he'll always be special.