The Live Wire

Because the developers actually acknowledge the fans. Like there's this one romhack of FE8 called FEGirls that FE13 may have lifted a lot of its ideas from. In FEGirls, they re-engineered one of the promotion items to be a reclassing item. Each class had limited options. It did all its work through the actual promotion system, resetting level to 1, etc. That's just one example - there's apparently so many things out there, that it's hard to call it accidental.

It's pretty much how it is in FE13 - the only difference being internal level being tracked so EXP continues to scale downwards. It also apparently has a lot of fandom in-jokes in Japanese, some of which carried over to English.