The first few times I heard someone say that they wear their heart (or feelings) on their shoulder, I merely assumed that they meant "on their sleeve" and had misspoken. But after a bit of googling I am now wondering if there are not some places in the US where people habitually use the expression "to wear one's heart/feelings on one's shoulder."
I expect that this expression is the result of confusing two different idioms. The person I heard use it is a college-educated professional from the Jacksonville FL area. According to rational-madness.blogspot.com/2006/07, Miss USA 2006 also used this expression:
At the recent Miss Universe pageant, when asked about her weakness, Miss USA answers, "I wear my heart on my shoulder... that keeps me humble."
I believe Miss USA 2006 was born in Dallas, TX, and lived most of her life up to the pageant in Russel Springs, KY, so perhaps this saying has some currency in the south.
In many of the examples I found on the Web, it seems to refer to having a tattoo of a heart on the shoulder, so context is also important. But apparently there are people who speak this way.
Can anyone confirm that this is the case, or is it really just a matter of a small number of people who habitually misspeak?