I've groomed my shelties myself for over 20 years also. Now I groom the rescues that come in. Some of them are in real bad shape. I've taken up to three hours removing mats and fecies from their fur before bathing just to retain as much coat as I can. Some times it's impossible to get them dematted then I use a clippers but only as a last resort.
This is a picture of my pack last September. Most of these dogs are already placed in forever homes but I wanted you to see just how much grooming I do in a week. I do a dog a day including my own...
It's a labor of love. It's work yes but I love a clean dog..
Hugs