At first blush, the whole plan sounds a little crazy -- if your intent is to pull back the curtain one on of the most pervasive surveillance operations in history, it seems just a bit naive to assume that the government being affected would be inclined to cut you some slack. Still, that's exactly what Snowden went for. He hoped that by thoughtfully making off with some files and only "touching" others, investigators would be able to tell that he wasn't a foreign spy poking around for sensitive data. Instead, he wanted to portray himself the same way he did after he first unleashed that load of information: as a whistleblower who only wanted to shine light on improper government practices.
Turns out, his moves weren't just meant to cover himself; he also intended those bread crumbs to give the NSA a shot at rebuilding its security and changing codenames to minimize damage from his leaks. That, obviously, didn't pan out. Those who were on his trail didn't managed to pick up on his plan and instead announced to the masses that Snowden accessed 1.7 million files in total, a figure that he (and his lawyer) think is way overblown.