There should definitely be something. I jumped a job myself, and wouldn't mind going through a trial as part of it regardless of my knowledge of the job. A lot of players who are jumping as brand new players are probably expecting something more like WoW where you can be at least passable with only a few buttons on many classes, then they log in and look at their bars like O_O uh...

...I'll just spam this one ability and hope nobody notices. >_>