A Mary-Sue is a character who is overpushed, hardly loses, and is pretty much the center of the show. It doesn't even HAVE to be an original CAW. It just usually is, since they tend to represent the feds owner, and friends of the owners.
To say you cannot push an original CAW without it being a Mary-Sue is completely ludicrous. In fact, the number of original CAWs pushed WITHOUT them being Mary-Sues far outnumbers the pushes where the CAW ends up being one.
Mary-Sues are generally a sign of poor booking and a swollen ego, and effectively causes whichever fed the character is featured as a Sue in to be an endless cycle of them winning World titles.
Mary-Sue's tend to have unorginal and cliche storylines that they follow, or just plain ridiculous and unrealistic storylines. They will often face only one or two problems (or maybe none) throughout their whole entire career. As stated above, they hardly lose, and, adding to this insult to CAW wrestling that is Mary-Sue/Gary-Stu, also don't get injured often because they are too "perfectly perfect" to get injured. In the case of the Mary-Sue, Tyson, he gets hit by a car and breaks his ribs. This is most likely a dumb add-on to his bio to add so-called "drama" to it.