JenP, no defence coming from me, but my Labs are after yah :D :D
Seriously I can see where this is all coming from. In most breeds there is an immense 'likeness' (for want of a better word), but in the Labradors there are so many varying 'looks'. Even Tia, in her gangly coming out of baby stage, was mistaken for a flatcoat

My dogs are show dogs, but I do work 2 of them and have had some strange conversations with some people on how they look ie; fit, not fat.
At a show on Sunday, I saw a beautiful white Bull Terrier but when he turned to display his rear end, I saw Emma, my yellow lab, as she is squat stocky and very highly muscled.
Compulsory DNA testing gets my vote, if it ever happens ;)