
I'm not a professional - so can only speak for stripping my own WT. You'll need to strip out the puppy coat to get the adult coat to grown though. These days exhibitors strip from 12 weeks (little at a time), but I went with my mums advice (she used to be a dog groomer back in 70's :P) and didn't start stripping mine until she was 6 months! Big error on my part as it meant she didn't have the coat for showing until she was 8 months - but you live and learn right? Haha
The more you strip - the more coarse the hair becomes, and the richer the colour. I left a patch on the back of my WTs neck for too long and it went grey, where as the back I was stripping once a week and it's jet black. An exhibitor friend laughted when he said he could tell I found the back easier to strip as it looked perfectly black compared to the neck which is harder to work! So the grey doesn't "grow out" you have to strip it off and alow the coarse black hairs to come though. I work on the rolling coat method - doing a little bit all over a few times a week (keeps her looking sensible all the time). Some strip completely bald in stages to achieve a correct coat. It's which ever you want to do :)
With a pup timing on the table is essential. Do 10 mins maximum, I got super strong setting out my table every day at the start :P They get bored easily - and the human gets fustrated! After 6 months of being stripped my WT finally stands nice on the table while I work on her.
So in essence. The puppy hair won't fall out - you have to strip it out. The adult coarse coat won't grown in until you strip the puppy hair. The more you strip the more rich the colours become. :D Hope that helped!