Well, to produce a Drum Horse, it should be a horse of heavy, draft type and with feather. Using a Friesian, would not likely produce the body type or feather desired. Most do not really consider Friesians, a true feathered breed. Also, most with top quality Friesians, do not breed them to other breeds, Rookie.
Oh yes PunksTank, in the UK for the last several years, it has been the fashion to breed smaller and smaller, 'mini' Gypsies. This by breeding to Shetlands and Minis. And of course, there are many who do such stupid things here too.