Just before the section entitled The Deming Affair, our good Bishop’s political hit job contains this other section, entitled The Medieval Warm Period becomes less warm.
This section contains three paragraphs, two long ones and a short one. In the first one, we get to know that Hughes and Diaz struck a major blow at Lamb’s view of climate history. The readers have not properly been introduced to Lamb’s idea on the matter, but will have to take our Bishop’s karaoke for gospel, even if two paragraphs later it is said that “it would take more than that to overturn an well-entrenched paradigm”, which sounds a bit odd considering the major blow foretold and the oxymoron “well-entrenched paradigm”.
The second paragraph is interesting enough to be quoted in full:
On its own, these findings might look interesting but otherwise unremarkable. But put in the context of the temperature history of the last thousand years their impact on the climate debate was potentially explosive. Anecdotally at least, the Medieval Warm Period, represented by the bump upwards in temperatures at the left hand side of the IPCC 1990 graph, was being slowly flatened out. And as it flattened, the current warming started to look more and more significant – if current temperatures were in excess of anything seen in previous times, it would be powerful evidence that manmade global warming had already had a serious and deleterious effect on the world’s climate. The flatter the representation of the medieval period in the temperature reconstructions, the scarier were the conclusion.
The emphasized sentence is interesting because it goes a bit further than what the auditing scientists usually say. For instance, here is a storyline proposed in one of the links of the post referenced above :
The IPCC 1990 graph is an important reference point. Ross and I have used it in presentations […] We said loud and clear that this is what the specialists thought in 1990 — providing a specific reference to IPCC 1990. You don’t imply that it’s what IPCC climate scientists are selling right now. Durkin could still use it as a segue to the visually appealing bits about the MWP and LIA by explaining that that’s what people thought only 16 years ago. After the graphics about the MWP and LIA, you can turn back to the graphic and observe — if this is what specialists thought in 1990, it certainly doesn’t convey any sense of urgency . It must have been hard/impossible to convey alarm with this as a sales graphic. You need good graphics to sell stock and this graph won’t sell stock. Then you segue into David Deming and “Get rid of the MWP”. [Queue in Deming schooling climate scientists into thinking he was one of them.] Maybe Jonathan Overpeck could be asked on the record about this quote. Then move along to 1998: just like the medieval king’s wish to be rid of the turbulent priest, there was someone ready to get rid of the MWP.
The expression emphasized is interesting, as we’re not sure to what exactly refers “what specialists thought in 1990″, even if it was said loud and clear.
If we consult the presentations by Steve and Ross, it’s not even clear that they’ve been appealing to IPCC 1990.
In any case, we can see that this “powerful story line” has been karaoked quite magnificiently in our Bishop’s political hit job. For once, we could hear the “unprecedented” fallacy loud and clear.
And speaking of being loud and clear:
[W]here in this post (or elsewhere) have I said that I accept this graphic? Read what I wrote rather than what you assume that I wrote. […] I observed only that this is what specialists thought in 1990 (as evidenced by its use in IPCC) before the Stick got oversold. 
It seems that sometimes, one can observe only, and that to only observe might be interpreted as “saying loud and clear that something is an important point”.
Perhaps it’s just a vocabulary thing.
 I believe that this answers Steve’s rhetorical question:
I do not think that any of the supposed refutations of the existence of the LIA and/or MWP are valid.
Please observe TCO’s loud and clear comment in the previous thread. Not that I accept it in any way, mind you.
 Update 2012-10-16: TCO’s comment was on the previous thread. Here it is:
Pete hits a point that I’ve wondered about. Just how good is that cartoony looking 1990 reconstruction that is often referred to?