Sounds far too complicated anyway. The last I heard at least 20% of people have no home internet connection. Surely is reasonable to assume that not all of the 20% have Sky, but that most of those people still have a TV. So what happens there then? Some sort of complicated system where people with an internet connection or Sky pay their their ISP or Sky but those that don't still have to pay a licence fee?
Why make the system much more complicated than it actually is?
A simpler system would be to fund the BBC from the treasury (ie through taxes) and introduce a rebate system for those who don't need a TV licence. After all the number of people who don't need a licence is much smaller than those who do.