I'll go out on a limb and state my opinion.
I believe we cannot babysit each other in our bidding. We can do our best and certainly we should comment when we see an invalid bid, but each of us is responsible for understanding how to bid. We've done it enough times now, we should have a decent sense of what is valid and what is invalid. The fact of the matter is Kalelen's bid was the most recent, valid bid. The player should be his in my humble opinion.
It's unfortuantely no one noticed the invalid bid on Ben Gordon until after the fact, but that alone does not make that last bid a valid bid. It was invalid and should be treated as such.
I'm sure this will come back to bite me on a player I really want. I'm just being up front. I think we should make efforts to try to help each other out and point out invalid bids, but ultimately we need to be held responsible for the validity of our own bids. And no more opening a player back up for bidding, etc. Invalid bids are withdrawn and ignored before awarding the player to the most recent, valid bid IMHO.