Even Sean Carroll may be right. He has written his
For example, the first commenter, Peter Fred, ignored the article. Instead, he proposed to replace dark matter by radial spreading of infrared luminosity, following the old-fashioned crackpot algorithms. Mark Trodden joked that Sean Carroll's revolutionary theory how to proceed was being ignored by the crackpot establishment and recommended him two simple steps how to be taken more seriously. ;-)
A few weeks ago, an alternative Iranian physicist came to my office and was explaining me that Dirac's paper on magnetic monopoles was mathematically inconsistent & light bending and general relativity were impossible, too. I was trying both to explain him these particular technical points as well as to give him a general "checklist" but it was probably a failure.
These people just can't concentrate on thinking. When you start to talk about the electromagnetic potential in the magnetic monopole background, he suddenly starts to talk about Lee Smolin who criticized string theory. It is impossible to explain him that his crackpot proposals about the magnetic monopoles and Lee Smolin's crackpot proposals about quantum gravity might be analogous at some spiritual level but they are separated by 70 years and there exists no logical connection between the two: if he sees a connection, he must be doing an error.
He asked me whether he should also see Cumrun and Nima and I told him that they probably wouldn't have time for him but he can always try: former countrymates may pay some special attention to him. After 10 seconds of a discussion with Cumrun, the alternative physicist got offended and started to scream that he was much smarter than Einstein and Dirac. That was enough for Cumrun to terminate the discussion. Cumrun left the office and he has only lost 30 seconds or so! The alternative physicist returned to my office to cry on my shoulder. ;-)
Nima spent 20 minutes with him, almost comparable to myself. He tried to be nice, just like me, but he found that our alternative colleague believes that all confirmations of Einstein's theories have always been conspiracies designed to support a popular figure. :-)