It can't hurt you. It can also be mentioned in your personal statement. Assuming your pre-SMP UG GPA is decent, plenty of schools won't hesitate to invite you for an interview/offer you a seat, with or without your SMP thanks to the high DAT. Of course, any admission will likely be contingent on completion of your program.
Where the SMP will help is getting interviews from schools that are on the fence about you. And those interviews will, on average, result in more positive outcomes. Even with pending grades, doing an SMP shows dedication and commitment. Some of them might offer you a pre-dec interview and wait for submission of your fall grades before making a decision. Other schools that would otherwise have denied you might wait to see your fall grades before offering a post-dec interview. As long as you don't bomb the SMP, you'll be in great shape.
Worst case, if you find yourself still wait-listed in March, you can start contacting adcoms using your SMP as a talking point. "I will be completing my Master's in May, got A's on my midterms, and am projected to finish the semester with a 4.0....."