[Bobbie]

This is a bit late to respond on this but at least in CPE and NADAC many corgis can jump 4 inches. While I agree that really hard-core competitiveness can push any dog, not just a corgi, too hard, I think agility can certainly be done safely with a corgi. There are plenty of older corgis out there that have been doing it for years and are still capable of running an agility course.

CPE is a nice venue for taking an easier approach to agility. They have the Specialist class, which allows virtually any corgi to jump at 4 inches at any age, and many games which allow you to avoid the A-frame (probably harder on most corgis than jumping) and still have fun competing. NADAC has a breed exemption and also a skilled class, so most corgis can jump 4 inches if you choose to do so. (Some corgis routinely jump 12 inches in competition; personally, I would not ask that of my dogs.)

As for back injuries, jumping OFF things like sofas and beds and out of cars is far more dangerous than jumping over things like jumps. But a corgi in good physical condition is less likely to be injured than one that is a couch potato and overweight.