What if Wayne didn't have psoriasis...
Then, he would've passed his physical at the induction center, and gone into the Army with Wart. Like Wart, there's a good chance that he would have been shipped off to Vietnam, and most likely would've seen action. It definitely would've changed the direction of the show.
So, what would've happened to Wayne? Would he have been dealt the same unfortunate cards as Brian Cooper? Would he have come home, physically in one piece, but psychologically traumatized, like Wart? Or, would he have been embittered, like Jack? Having said that, if Wayne and Wart had both gone to fight in Vietnam, and both had come home, would Wayne have been in a better or worse position to understand what Wart was going through, and help him readjust to civilian life (probably much better, I'm thinking)? If Wayne and Wart had both been sent to Vietnam, would they have killed off Wart, leaving Wayne traumatized? Would Wayne still have followed Jack's civilian career path, after getting discharged (NORCOM, then the furniture factory)? Do you think that if he had been in the military, then he wouldn't have been so dependent on Jack's job for his own employment, because he would have had more self-discipline and motivation?