I didn't mention skype connect.
>the win/win for sype/sip providers is only when the calls go through PSTN beween them.
Do you really think the operators of skype or the sip providers cut the PSTN people in for anything when they don't have to? The only direct through pstn as a last resort.
I have called peoples skype-in numbers from my skype account. I do get charged for this. I am certain it goes through no pstn network.