I've had a strong dislike for glibness for a very long time. As with all communication the key is not what is said but what is heard. I think glibness is so dangerous because it is a lie wrapped in a truth.
"Smile, Jesus loves you" definitely contains much truth. Jesus loves you more than you can possible imagine and that truth is the source of much joy, but most often when someone says that what they are saying - or rather what is heard is very different.
Glibness is this: "Your pain makes me feel uncomfortable so please can you pretend to feel better so I don't have to be uncomfortable..."