Gosh, you're definitely onto something there. Can't believe Nintendo didn't think of that. And no one else in this thread has thought of doing that! You're a genius, we'll have an exploit in a matter of hoursI just realized how stupid Nintendo is to put 3DS digital downloads on the SD card. Now we can examine the contents of the software and possibly find an exploit!
Note: This is sarcasm. Nintendo did nothing in the slightest bit stupid. The files on SD are encrypted and signed (probably several times, judging by the Wii). There is no way you are going to be able to decrypt them without knowing at least the 3DS common key, and probably a few others as well (SD key, maybe a per-console key specific to your device). None of these are common knowledge. So good luck with that.