I saw a lot of people were confused about it in the Raw thread. Vince said Johnny signed the wrong one-legged wrestler to a contract. Zach Gowen wasn't the mistake.
It's supposedly an urban legend but I guess it is true.
In early 2003, rookie "Tenacious Z" Zach Gowen was making a name for himself on Midwest independent wrestling scene. It wasn't hard for him to stand out: He was a pretty good high flier who only had one leg.
While he lost his left leg to cancer as a child, he was a good athlete and became proficient at various flips on a trampoline, even when he he didn't have his prosthesis on. He started training at current Ring of Honor manager Truth Martini's wrestling school after he turned 18 and started wrestling (again, without his prosthesis) a couple weeks before his 19th birthday.
In early 2003, he made a couple appearances for TNA, but like many wrestlers who made a shot or two with TNA, he didn't have a contract. With his buzz increasing, WWE talent scouts wanted to sign him before TNA did and told John Laurinaitis (who was being groomed to replace Jim Ross as Vice President of Talent Relations) to sign the one-legged guy they had been hearing.about.
Laurinaitis made some calls to try to find the one-legged guy. A native Floridian, he spoke to some friends who directed him to Steve Chamberland, a big, burly one-legged wrestler who lost the limb in question in a motorcycle accident and wrestled with his prosthesis on.
So yes, not only did he get in touch with the wrong one-legged guy, but the wrong one-legged guy was the complete opposite of Zach Gowen and nobody had ever heard of him.
Nowadays, the urban legend is that Laurinaitis signed Chamberland to a WWE contract. I'd love to confirm that to put the cherry on top of this story, but according to a contemporary report from PWTorch.com, it never got that far.