The real story is that Chris hated having his head shaved. After a few weeks, his scalp would get tender and it would hurt to be shaved. In fact, when he first screen tested for Teal'c, he very long hair. (Did he say they were dreadlocks or did I make that up since I had a flashover vision of Keith Hamilton Cobb when he said that?) But Stargate didn't call and didn't call and Chris had to make the professional decision to go to L.A. to try to get work during pilot season. Thus, the hair had to go. And, of course, THAT is when Stargate called.