I just saw a video on SMP over at Dr. Rassman's Baldingblog.com
As it turns out, some people are utilizing this technique to make their hair look thicker should they suffer from a lack of donor area. (No follow-up on that case yet). In addition, it appears that SMP may be a good way to hide donor scaring that many people suffer from.
It will be interesting to see where this goes over time.