I think this would be very beneficial for farm parties who want to keep out those people who try to hide and get their clears.

And to those who think that exclusion is bad, take a look at the "required ilvl" stat needed to join parties anyways.

In the meantime until this gets implemented, once you form the party you must type into the party chat "this is not a clear party, all players must have a clear to be here." If you type this and someone is still in the party without the clear, you have legitimate grounds to report them to the GM, since it was clearly stated to all members.