[John Mashey analyzes an important blog post surrounding the Deming Affair. I’ve edited a bit for clarity (I know, I know).]
You don’t have to go into statistical problems, as per DC’s Replication and Due Diligence … or Nick Stokes on selection , i.e., wrong parameters and 1:100 cherry picks.
Here’s a no-stats case: The Significance of the Hockey Stick, Mar 16, 2005 at Climate Audit  plus a few related talks shortly thereafter.
False Citation and Flat Earth Schematic
McIntyre shows the ~1965 Lamb graph, used once by 1990 IPCC (Figure 7.1.c, with caveats in text, unclear whether ever read.) It had disappeared by 1992 Supplementary Report, and certainly was not in the 1995 IPCC, whose Figure 3.20, p.175 had an early reconstruction back to 1400AD. Maybe someone should ask McIntyre where he actually got this schematic from, because it was not the 1995 IPCC. The 1990/1995 date matters, seen later. See Jones, etal, Appendix A  for the history of the schematic, which dates back to H.H. Lamb ~1965 on Central England, which is certainly not the NH. (Referenced IPCC reports are here .)
Anyone citing this schematic as credible any time after 1992 might be likened to a flat-earther clinging to Anaximander . Think of the schematic as a flat-earth temperature sketch, which by 2005 got retroactively elevated (by a few people) and promoted as Absolute and Unchanging Truth being hidden by a cabal of climate scientists, just as the way NASA is hiding the absolute truths known by the Flat Earth Society . There we find The Conspiracy :, the active faking of the whole space program, not just Apollo! It has a good FAQ . They show a newer map than Anaximander, still flat.
Use of Unsubstantiated Claim Published in a “Dog Astrology Journal
[McIntyre] actually cited as a preprint at Fred Singer’s Website, in a glowing review of a fiction book by a geologist of strong views, David Deming , author of Why I Deny Global Warming , which starts:
I’m a denier for several reasons. There is no substantive evidence that he planet has warmed significantly or that any significant warming will occur in the future. If any warming does occur, it likely will be concentrated at higher latitudes and therefore be beneficial. Climate research has largely degenerated into pathological science, and the coverage of global warming in the media is tendentious to the point of being fraudulent. Anyone who is an honest and competent scientist must be a denier.
McIntyre took the key quote from Fred Singer’s SEPP Website , where it appeared March 5, 2005, ~3 months before it was actually published in Journal of Scientific Exploration (JSE) . This was a curious publishing practice and seems to have violated policy :
The material must not appear anywhere else (including on an Internet website) until it has been published by the Journal (or rejected for publication).
Singer and McIntyre were in contact no later than 2003. Deming cited McIntyre and McKitrick (2003), and McI+McK made use of Deming’s citation of Huang, et al on boreholes (see below).
JSE as “Dog Astrology Journal”
JSE often publishes on UFOs, ESP, reincarnation, etc , but more interestingly on dog astrology. See commentary on Deming’s other articles in JSE and other articles in same issue . Occasionally, a serious debunk (as of crop circles) is seen, but sampling the articles may help the reader assess overall credibility. (Philosophically, I’m happy that someone looks at anomalies, but the reader can study articles here and estimate how many are by people with long-cherished ideas lamenting mainstream science’s unwillingness to accept them, publish their papers, etc. See abduction research , for example.)
JSE has also published Joel Kauffman’s Climate Change Reexamined . See comments here  and here . Kauffman:
Because of the existence of a research cartel and media control in this field (Bauer, 2004), the readers’ forbearance in my use of websites and non-refereed sources is requested. […] An example of non-scientific pressure in the climate field is the firing of six editors by the publisher of the journal Climate Research because they published a literature review on long-term temperature proxy studies (Soon & Baliunas, 2003). …”
Kauffman was rather confused about the PALS case . The reader may assess reasons why emeritus-chemist Kauffman’s work on climate might be hard to get published and the reader might want to assess the quality of peer review on climate-related papers at JSE.
Deming has not produced any evidence of the email he claimed to have gotten in 1995. His views are certainly clear.
McIntyre post and talk
If McIntyre in 2005 had properly labeled the schematic as long since deprecated, gone by 1992, with modern work starting by 1995 IPCC, it would have been obvious that scientists had discarded it like a flat-earth map. That would have made Deming’s 2005 claim of a 1995 email look silly:
a) Nobody in 1995 would have been worried about “getting rid of the MWP,” although they might have wanted to dispel the idea the Lamb schematic was Truth. They had years before abandoned the schematic.
b) Most reconstructions since (including MBH99) had a modest hemispheric MWP, in fact, MBH99 was higher than many. Perhaps readers understand why one would expect decreasing jiggles going from a) Central England or further North to b) half of Northern Hemisphere to c) entire NH to d) world.
The themes of Lamb schematic=Truth and conspiracy by climate scientist cabal show up in the Wegman Report, whose “blueprint” was May 11 2005  presentation in Washington for Cooler Heads Coalition (CEI) and George Marshall Institute, and then somewhere on Capitol Hill. Hence, all this actually matters, since it was used to mislead Congress.
McKitrick had gotten the 1990/1995 problem wrong in this an April 4, 2005 talk , but fixed it ~July 2005  McIntyre did not go back and fix the blog post. Mckitrick cited both Science and JSE correctly in April, but by May (p.12), McIntyre was attributing Deming’s 2005 JSE quote to Science 1995. That persisted in George Marshall institute’s later edited transcript version, p.6 . Replacing JSE with one of the world’s top two general science journals is another false citation.
The Huang, et al borehole discussion is another flat-earth graph, shown in SSWR, Appendix W.4.3 , too long for here, but an example of clinging to an older article one likes, ignoring the same authors’ more recent work that contradicts it.
To summarize, in one short McIntyre blog post, we find:
reliance on flat-earth schematic, obsolete for 13+ years.
reliance on dog astrology journal preprint via Singer
And then we find a talk in which JSE becomes Science.
I leave it to the reader to weigh the possible explanations for all this.