Hi Bitsy - I am sorry your feelings were hurt at the groomers, been there done that years ago with my Schnauzer.
I was wondering if maybe it's not the shampoo/conditioner you are using but the type of hairbrush.
I have found that a slicker brush works wonders on Schatzie and Annabelle my Schnauzer. The brush does get to their skin (be careful not to push too hard though) and it really brushes out the coat nicely.
Just a thought...
Oh and yes, the Vellus might seem pricey, but it's so concentrated. Vellus should last you quite a long long time.