[What do abilities/classes do in this game, really?]

So I know it might seem like a stupid answer, but what I really mean is the ability you get when you master a class. I found out that its class specific. For example, I leveled Petra up to max out Theif, but when I change her into a mercenary, her steal ability is gone. So what's the point of maxing out your class? What if I get too many abilities and i wanna trade one out for a new one? Is there a way to keep your abilities, of so how? I know that there are leveling stats the differ based on what class you're in, bit is that it? What's the benefit of mastering out a class? Sorry if this is confusing, it's just that I've never been confused with a class system before xD

 

[Who did you dancer and why?]

8 hours ago, Jayvee94 said:

I don't think he's officially in your class. He's just helping with your class.

Is there a way to make him in your class.....? I doubt it 😞 but it's weird because he also attends my lectures and when I click roster he shows up. Are you sure that's the issue? Like I said, it probably is the issue but idk.....had to replay 5 hours worth of gameplay because I forgot to recruit him before the cup so maybe I'm just desperate xD

[Who did you dancer and why?]

Please help....im trying to get Cyril to be my dancer but he isnt responding to me when i talk to him when im supposed to. I know its nothing to do with his charm because i've asked dedue, who only has 8, has offered to be the representative. Cyril, on the other hand, has 11.....please help <_>