It is not terrifying per se, just ... very different.<p>I have only had brief contact with JCL, but I remember having to figure out how to get a command line into JCL that was more than 80 characters in length. It took me two days to figure that out, and none of the old-timers in the team had ever had to do that. When I <i>did</i> find the solution, it was surprisingly simple, but finding it took me a lot of time.