To be fair to the poor guy (yeah, I actually feel sorry for him at times), the Constitution does give Congress explicit control over naturalization. Given that permanent residency usually ends up with its holders naturalizing as U.S. citizens, it won't look pretty if President Obama gives anyone a chance to adjust status to permanent resident. The courts won't stand for it, not to mention Congress, whether Republican or Democrat. The best the President can probably do is give deferred action of some kind, notwithstanding some other change Executive Agencies can make as to how they understand some phrases related to the 3- and 10-year bans.