Healers, Blue Healers, Red Healers, ACD, Stumpy tails - all fairly common names for cattle dogs - some even call them cattle dogs!
Kelpies are used for gathering and bringing stock while healers are used for driving - at least that is what their instinct is. You can teach kelpies to drive and healers to bring but that is not their first instinct. Kelpies do tend to be slightly finer then healers but not always. Tilly is very solid for a "modern" Kelpie but not for an older style kelpie. The general trend at the moment is to breed working dogs smaller so that they can ride on a bike easier (4 wheeler) - there are other reasons but this is what I've been quoted time and again.