The major problem with ticket 16276 is that it isn't a fix (as you seek here). It just moves the current implementation into the details document rather than being done in the node index. I don't think you *can* fix it as you seek. Bi-directionality isn't an enforceable property. The spec makes no guarantee. The internet makes no guarantee. You might as well remove the family property entirely than try to do what you suggest.
What you propose isn't possible by the properties of tor's network. The best you can do is take a measurement and hope it applies to all views of the network. I made some comments alluding to this in 16276. I would happily work on the ticket if it actually presented a solution.
Comments appreciated. --leeroy