I'm a firm beleiver any dog should be first and foremost healthy and able to do the job the breed was intended for in the case of a yorkie it should be able to catch and kill rats. Any under the size to fulfill this criteria should not be being deliberately bred. I voted any under 5 lbs to be tiny/small/"teacup". I'd like to think the "craze" for really tiny dogs will not be here for ever or we could see the end of the Yorkshire Terrier/ Maltese/ Chihuahua as good sound breeds of dog
