[crote]

Absolutely not. Why would they spend a significant amount of time and effort engineering a special mode which is far more complicated, less secure, and will rarely be used?

And how is it even supposed to work? How are you going to handle billing? Does a cell phone tower even know the phone number of the connected devices? What's going to happen when the recipient disconnects mid-SMS? What happens when the same number is in use by multiple SIM cards?