Having a low SMP grade is almost a nail in the coffin, because you just confirmed to the adcoms with actual medical school grades, that you couldn't handle the coursework. (This is also assuming that your SMP grades are not as a result of documented illness, etc..etc..) Granted a 2.91 isn't so terrible when it comes to medical school grades since most medical students just get P's on their courses which could be the equivalent of a around a 3.0 but because you are held to a different expectation, you're expected to do better. Did that 4.00 in your MPH come after your MS? The problem with the SMP is that its one of those, "last things" you can do to get into medical school, that is, save the best for last: it is the most powerful way to enhance your application and has sent kids with non-competitive GPAs (such as myself) into medical school with good SMP grades. If you don't do well in it, you essentially tell adcoms that you couldn't excel in those medical school classes. Now granted, I'm sure people have made their way into medical school somehow with low SMP grades, but these are probably in the minority. I suppose that it works in your favor that your undergraduate GPA is OK, and your MCAT is strong- this might give you a leg up.
It will be extremely difficult to overcome poor grades in an SMP. I suggest taking a look at applying off-shore, and adding in DO schools as well as applying (early of course) to a broad range of MD schools in the US. Start by looking through the postbac forums (I am the moderator there) to look on success stories following poor SMP performance. Another consideration is to retake the MCAT (you would never otherwise see me tell anyone to retake the MCAT over a 30) and knock it out of the ballpark so that the emphasis falls off your low SMP grades. As well you should also consider an alternative career choices and perhaps reapply later in your life as a non-trad with working experience. Finding residency in states like Ohio or Texas and perhaps NY may also help as an in-state resident. Those are things that I would imagine can help benefit your application, but to be honest, I've always been told by many SMP faculty across different schools that doing poorly in the SMP is a surefire way to close the door into getting into medical school. There are always exceptions but it will certainly be a difficult task. Good luck and feel free to PM me.
