Comment Certainly nothing new... (Score 2, Informative) 135
I bought a corded earpiece for my cellphone many years ago which was made by Jabra (http://www.jabra.com) and I believe it worked on the same principle. It had no external microphone and when I talked on it people said it sounded as if I was talking from a landline even when blasting down the freeway under high road and engine noise. The people at the other end had no idea.
I loved this earpiece, but sadly I can't seem to find many of these types anymore in a wireless configuration.