Appropriate Signal to Noise Ratio for CMB Measurements? (Wmap, Cobe, Planck)

I'm fairly unfamiliar with data processing and data analysis in astrophysics so i'm unsure how to address certain claims as to the veracity of astronomical measurements. The paper by a crank physicist named Pierre-Marie Robitaille got me thinking. What is a respectable signal to noise ratio in astrophysics and, in particular, why a ratio of less than 2:1 for the Wmap data could be then considered an accurate recording of the CMB? What could be considered a standard in astrophysics for a signal to noise ratio that would indicate an accurate reading? If you could supply some extra reading material at the undergraduate level i'd appreciate it. 

802260431_PierrePaper.pdf