Originally Posted by Abby
Very very rare is that a possibility. Not only that but if he had missed one your gelding would be trying to breed mares if he had the chance, because although he only has one testicle, he still has an active supply of testosterone meaning he will have a stallion libido. HOWEVER. One thing that MAY be possible would be that he cut to too far from the base of the testicles.The closer the cut to the horses body the less stallion like he will be. If he was cut far from his body, then he will have more stallion like tendencies.
I'm not sure where I heard that but I have found it to be true.
30% of geldings (I got this statistic from Horse & Rider Magazine, I didn't make it up) retain (noticeable) stallion like tendencies throughout their life. He may be one of those geldings.
just to let you guys know, I almost bought a horse that I thought was a gelding, he was studdish with the ladies (arch his neck and puff out) along with a lot of talking, he would get defensive with the stallions at the show, well I did not purchase him because of soundness issues. He was then sold as trail riding sound only. The new owners turned him out with a group of Arab mares, and sure enough, he bred all of the mares, he was an inverted gelding. (he had both of his boy parts there, just up inside, they did not drop!) they said it cost them a lot more money to have him gelded. So it is possible.