Ok, so Mark Erwin DC PhD.
Not an MD so not a clinician. PhD is a very varied term, so let's look at his pubs (as you do with any researcher regardless of title)
Standaert C, Friedly J, Rechtine G, Erwin WM, Lee M, Hennrickson N and Norvell DC Comparative Effectiveness of Exercise, Acupuncture and Spinal Manipulation for Low Back Pain: Spine 1 October 2011 - Volume 36 - Issue - p S120S130 doi: 10.1097/BRS.0b013e31822ef878
Found in Spine, a 2.0 impact factor journal which DOES reach clinicians.
Conclusion:
The studies identified indicate that structured exercise and SMT appear to offer equivalent benefits in terms of pain and functional improvement for those with chronic LBP with clinical benefits evident within 8 weeks of care. However, the level of evidence is low. There is insufficient evidence to comment on the relative benefit of acupuncture compared with either structured exercise or SMT or to address the differential effects of structured exercise, SMT, or acupuncture for specific subgroups of individuals with chronic LBP. There is also insufficient evidence regarding the relative cost-effectiveness of structured exercise, SMT, or acupuncture in the treatment of chronic LBP.
Hmmmmmmm.....
He also has a series of mouse model papers with real quantifiable methods which do not set out to prove anything but rather seem to interpret things freely (and even seem to debunk in the case of this meta). All things that I had said previously, that the research can very well be good if and only if the researcher is not attempting to validate a pre-held belief.
Once again, your point that "DCs are out there who do meaningful work" is entirely meaningless in the greater context of the thread which was "those DCs who peddle garbage are a threat to public health". This guy's paper claims that a cheaper gym membership is as good for your back pain symptoms (let alone the plethora of other things it is good for) as chiropractic adjustment.
He isn't the problem by the claims and definitions I have set forward numerous times in this thread.
http://www.ncbi.nlm.nih.gov/pubmed/22705752 another good one that clearly suggests this guy doesn't buy the subluxation mantra.
Moving on:
Pierre Cote, DC.
He seems to have quite a few papers related to public health and a few reviews.
J David Cassidy: He has published almost exclusively reviews (not of real value, just restating the portions of the literature that he finds pertinent).
your MD/DC guy has only 2 papers, one of which is a simple case review. Not terribly interesting and not terribly illuminating as to his motivations for switching.
The point is, I had to do some pretty major digging in order to get the papers these guys have been involved in. Many are doing nothing more than writing comments to ortho and neurosurgical journals complaining when someone publishes a paper that disagrees with their "religion" (a few did this.... and they have nothing other than a few outdated studies or interesting twists on their own literature reviews to land NOT on the conclusion that manipulation is beneficial but only to cast doubt on some researchers claims that it is harmful
)
So when you post a list of these guys and say something to the tune of "why all the hate for DCs? See? They do lot's of good work" and the only way to justify that claim is to spend the better part of an hour digging into and searching out their pubs I would say yeah... you failed to support your claim. Coming back with "well you need to do the legwork before claiming my point as unsupported" is entirely invalid on the basis that I didn't say you were wrong, just said you failed to show with any certainty that you were right.
The burden of proof is on you when you make a claim, not on me when I says you failed to do so. But since I went ahead and found it for you, you have 1 MD who seems to be largely just a clinician, a few with PhDs, 1 who is publishing
against manipulation or at the very very least not in favor of, and several who are writing into journals with "letters to the editor" who are complaining when they see published articles that say something other than their medichlorian count is super high.
So yeah.... not meaningful work in most senses and certainly not meaningful in a way that would shame anyone for being critical of the field.