Well, the fact of the matter is, everything I found in regards to this follows a pattern.
Everything I found is non-theoretical and your entire argument is.
Never did I say that because I find religion silly, those with one are savage murderers and rapists. Rather, I put in some effort and discovered the undeniable and consistent facts that there is indeed a correlation between religion and crime. Whether that means if someone has a religion they are more likely to murder or rape , or just do the "big stuff" like suicide bombings, major assassinations, mutilation and so on, I can't say.
-And also, If there where such statistic about handedness and retardation , there might just be a biological reason behind it. At least I would bother to try to find out, rather than being like you and just dismissing it because it doesn't sound pleasant.