This is probably my 5th time through the series and I didn't notice this little continuity glitch before now. Just watched Broken Link. "I'm reading a heart...lungs...it's almost as if he's human!" But in other episodes it's established that when you scan a changeling taking the form of a human you scan a human. If that weren't the case, Homefront would be a very different episode. "There are 4 changelings on Earth." "Okay scanning the planet for changelings, there they are! Beaming them into an airtight room." Also Odo mentioned at one point "When you scan a changeling taking the form of a rock you scan a rock." Why was Bashir surprised to scan human internal organs in Odo?