who made the video you purchased? just curious. i haven't watched any on yorkies.
Like Gemy, the only slicker i use on a yorkie is the tiny soft CC slicker brush, and that's only on mats with lots of detangling spray. I don't drag it through the hair but do more of a tap and pull method. then i use a stainless steel comb. I mostly use either a CC t-brush or the wooden pin brush on most dogs. i find they break the coat less which prevents future matting.
Slickers
I have the x-small and my boss has the tiny. both are very very soft compared to other brands.
Pin Brushes
20mm small wood pin brush in purple
16mm t-brush
Combs & Handles
#000 Buttercomb
I also like CC Ice on Ice or Nature's Specialty Quicker Slicker as a leave in conditioner/detangling spray for combing/brushing/dematting.