Darlene, I think I have the same grooming video you bought and I could not watch the woman working with the slicker brush on the dogs' faces. I had to turn it off.
I tried a small slicker on Teddy when his hair was going through changes, but I found working with a rat tail comb much more effective. I still use the rat tail to carefully break up tight tangles.
My favorite tools are the ISINIS brush (learned of it from Mary) and the CC Buttercomb for face/legs. I gave my father one of the brushes and it cured the cowlicks in his silver hair.
