[LunarBerry]

Cutting the hair at a young age does not stunt hair growth, if ya actually pulled alot of hair out from the roots or damaged the skin area, then maybe it's possible. Yorkie hair is alot like our hair, if the hair has issues then there's either an underlying issue (like health) or an outward one (matting, dryness, etc.). Granted I know grooming and cosmetology is different in alot of ways, but I would think that the hair follicles would essentially work in a similar manner, human or yorkie. If the hair was going to be stunted, it's gonna be stunted by other means, not from cutting the hair itself.
But on the thread subject, lol I keep my girl's hair mostly short but in winter I'll let it grow out some. She get's hot fairly easy.