TwinqeEdit: They have scaling to level 50. The effect is the same as if it were 100, so battling is still accessible even if your pokemon aren't max level, assuming you have EV trained them.
You're pretty much bang-on with that, but if we want to get kinda finicky with numbers (and hey, this is a Pokemon thread) I believe the 50 flat battles slightly skew stats by one or two points: something to do with the 252/252/8 spread being halved. In short, there's an optimal way to get EVs for flat battling and another optimal way to get EVs for standard play.
Again, not something to be awfully concerned about but it's there.
Also, yeah, try to avoid posting links to ROMs and the like. Regardless of whether or not you agree with intentions of posting it, the fact remains that it doesn't belong here.