I've had excellent results with a similar process. I go over the interior and spot treat stuff with Folex and a couple microfibers. That wipes up most of the stains but leaves the Folex on there cause it's still a little damp. Then I'll spray a seat down with blue coral foam, go over the seat with a stiff brush attachment on my DA, let it dry out, and vacuum to clean up all the stuff the brush pulled out. That takes care of most of the stains I've come across and they dry even and nicely fluffed up from the brushing. And I haven't had issues with anything reappearing once dried. If anything didn't want to come out then I'll go at it with my steamer and some APC or degreaser.
I used this process on a 10 year old trashed Taurus and it came out awesome. Pics are from a couple photos i threw together to share on my Facebook page but they show before and afters.