Because mine can't. So is one of those passme or what have you required to boot even a legit slot 2 games? When I put in Minish Cap, for example, and select load slot 2 on the R4 menu, it won't load. It just goes a white screen. Now, the DS reads the game, as evidenced when I boot without the R4 in.
EDIT: I'm mostly concerned with Pokemon Diamond/Pearl. I know that you can use your old GBA games to transfer over pokes. So, even if my R4 can't directly read a GBA game (or boot it, I dunno), will I still be able to transfer pokes from my (legit) Ruby copy to a flashed Diamond/Pearl?
EDIT: I'm mostly concerned with Pokemon Diamond/Pearl. I know that you can use your old GBA games to transfer over pokes. So, even if my R4 can't directly read a GBA game (or boot it, I dunno), will I still be able to transfer pokes from my (legit) Ruby copy to a flashed Diamond/Pearl?