Oceans heating, but how deep?

RealClimate: Global warming and ocean heat content

This Real Climate post, and the comments and discussion following, are important.  The issue is heat going into the oceans, and whether once it gets there, it is possibly a problem again in the future.

There has been a skeptic argument around that if upper ocean heat is getting "buried" in the deep ocean (a fact which itself is very hard to measure, apparently) then the heat does not represent any future "threat" to surface temperatures again.  Yet Trenberth had made a statement that any heat going down "has not disappeared and so it cannot be ignored. It must have consequences.” 

Gavin Schmidt seems to indicate that, whatever Trenberth had in mind (and, curiously, he doesn't seem to know exactly what it was,) heating of the deep ocean has never been considered a threat to surface temperature.

Roger Pielke Snr turns up in the thread too, and Schmidt dismisses most of he claims about Ocean Heat Content.  In particular, he says the ARGO system simply can't measure ocean heat moving from the top layer of the ocean to the deep ocean, whereas a skeptic meme (started by Pielke, I think) is that the "missing heat" can't be going into the deep ocean because ARGO hasn't seen it passing through the top 700 m.

This really does appear to be a very complicated topic, and it is surprising to see that this may be a case where climate scientists have contributed to a skeptic meme via their own looseness of language.