Early Takeoff Syndrome.
No, I do not believe there is a true medical syndrome that is defined by "bad jumping". But I do believe we need a name for this strange collection of symptoms that affects some dogs. I had a dog such as this. Many people won't remember her at all, because I retired her early and allowed her to go live with a nice retired couple and be spoiled. Freeze was a highly intelligent dog, very athletic. But she was a poor jumper. I have worked on jump grids and lots of 1 and 2 jump exercises with my dogs since the dark ages of agility in the early 90's. Freeze did many a jump grid and lots of exercises. She was fit. She passed her CERF exam. She was smart, she was well-trained. She achieved her ADCH title relatively quickly, qualified for USDAA Nationals every year I ran her, made a few Top Ten lists, and even got an LAA-Bronze award.
Freeze had ETS. It is a painful problem to work with. And no, it isn't JUST a matter of training, it isn't even JUST a matter of agility. There are a lot of situations where a dog needs the ability to judge a horizontal "bar" of some sort in space, and she had trouble with all of the. Open types of stairs scared her a bit. She was quite concerned about entering and exiting small crate doors, and always flew through them at 90mph.
Like many ETS dogs, Freeze had a softer personality type, and if I even THOUGHT about correcting her knocked bar, more bars were sure to fall. Also like many ETS dogs, she was highly sensitive to my motion while she was jumping. If she knew I was about to front cross, the bar fell down. If I tried to lead out too far, the bar came down. If I did anything in front of her, basically, the bar came down. So I used a lot of rear crosses (which unfortunately led to people thinking I was unable to handle using front crosses, when in fact I generally prefer to work in front of my dogs!)
Linda is continuing her work with ETS and has been updating the information, adding a new webpage with some newer video links. Because I am now considered a "big name" agility handler (woohoo I guess I've made it!) and I had an ETS dog, i was asked to put some video together showing the problem. I gladly complied. I think it is a sad state of affairs when other "big name" trainers claim that ETS is just an uneducated dog, or one that's rushing. Clearly these people are blind to the obvious anxiety that can be seen on the dogs' faces as they attempt to figure out where the jump or tire is. Many of these dogs have a big heart, and enjoy working with their handler so much that they continue to try, but clearly the dog is just unable to judge things properly. Training can not overcome physical issues, whether they are due merely to vision problems, or to some strange connection between vision and brain.
Here is the video of Freeze. Some of it is quite cringe-inducing and looking back, I am very glad that I allowed her to retire before she got any worse.
ETA: I want to clarify that while I don't believe "bad jumping" is an inherited issue, I absolutely do believe that the collection of traits which lead to this problem ARE inherited. i think it's undeniable that some related dogs, who were bred by different people and raised in different homes, still develop the same problem. ETS is caused by something which is genetic.