You are not really maintaining that Russian Muslims are not significantly out-reproducing Russian non-Muslims?
You clearly have misstated my assertion.
What I am claiming is that Russian non-Muslim birth rates are accelerating, while Muslim birth rates in Russia are
decelerating. I'm talking about the picture in time - as in the change from 2005-2006-2007-2008. A link from 2005, even if it points out Muslim birth rates being 10 times Russian birth rates, would not disprove or prove my point.
In addition, the Mufti's claim that '20% of Russians are Muslim' is also not based on any research.. The Russian census counts only ethnicities - about 10%-14% of Russia's inhabitants (including non-citizens) belong to ethnicities that are 'traditionally' expected to be Muslim. Not all are.
It's known that anywhere from 10-15% of those 'ethnic Muslims' are actually worshipping other faiths, like Orthodox Christianity, and many are even atheists. (That's 1.4-1.6 million people who are 'supposed' statistically to be Muslims but are actually not).