Actually, it could.
Say the experienced cop has a good reason to be suspicious that "something's" in the trunk (drugs, bank money, kidnapped child, whatever). Say the driver has a criminal history, is acting nervous, keeps glancing at the trunk, has "lost" the trunk keys, etc.
Without the availability of a legal dog search, the cop would then have to seize the car, have it towed, get a court order, and search the trunk. Eerything nice and legal, yes? Oops, they find kiddie porn.
Well, I say the driver would have more privacy and protection if they bring the drug sniffing dog. No reaction, you're on your way.
It would be doubtful that a cop could ever obtain a court order under these circumstances as these conditions fall far short of "probable cause".
I am sure that some rubber stamp judges do would approve though, but that would be a perversion of what a reasonable person would consider probable cause