IMO dogs should 'drop' their coat only once or twice a year, although they will lose hair to a certain extent all year round, but not excessively.
My 'teenager' is just blowing his coat for the first time, I stripped him out, bathed him, then dried him with a blaster which blew out the remaining loose undercoat. He now looks like a different breed of dog...LOL !, but his skin is clean and fresh to start growing his new wardrobe.
I think a good diet and adequate oils on a daily basis are necessary to avoid excessive moulting.