To my mind, the best way of exposing the strengths or weaknesses of ideas is to see them challenged openly and honestly by people who know what they are talking about.
PZ Myers and his fan club are a collection of people used to - and very good at - arguing with creationists and so they see themselves as hard-core skeptics. I would be there with them too on 99% of issues but, bizarrely, as PZ has come down so heavily (in my view through ignorance) against these ideas I had to go there to oppose him.
I feel it is a duty to put ones ideas up against the most hostile and knowledgable people one can think of to see if there are any gaping holes in them.
At the end of the day, if someone had come up with a really good argument against my modest waterside ideas I'd drop them straight away. The closest they came was Amphiox citing the Myoglobin paper. It's a brilliant piece of work which should cause those people who argue for a lot of diving in human ancestry to really think again, in my view. The manattee/dugong outlier is a let off but the point about their "slow metabolism" cannot be dismissed easily if one is postulating a lot of diving for Homo erectus
. My view is that humans did only a little diving, so there is no need to postulate any reason for our myoglobin to have evolved along the same lines as other more aquatic mammals, but the result of the paper was still rather surprising. I'd expect humans to be closer to aquatics than chimps, but it's the opposite. The paper mentioned that it is possible that there might be a reversal in the trend at first, before real selection for diving kicked in but I don't think any of us can pretend this is not a damaging paper to waterside ideas. If the results had shown manatees and dugongs as also very different from humans, I think I'd be seriously thinking about dropping the whole idea now.
Apart from that, fortuitous for them, paper that just happenned to be published during the discussions, I don't think the aquaskeptic lobby came away looking good from an informed, neutral point of view. Out of about 2,000 posts, mosts showed denial of what I consider the most blatant evidence imaginable - we do swim and dive better than chimps. Many were bent on simply distorting the ideas - again and again, despite repeated corrections. And in the end the refuge of their group think sneering was to sneer and to throw hostile names as us.
I see that part of it as a victory. Even if 100 PZ fans had turned up to deny the evidence, twist the arguments and throw slurs to discredit, it wouldn't make their argument one bit stronger. Unfortunately for us, the Myoglobin paper did that and I for one have to admit that this damages the "diving made us human" idea quite severely.
If any diving proponents read this and can think of something I've missed I'd be pleased to read it.