Well, you have qualified your start more than a tad. Starting with both stone and marble in your capital's Big Fat Cross is certainly possible, but largely improbable. And yes, that would skew the calculation in favor of some religious techs earlier rather than later in most situations.
However, we are talking noob advice here(or at least I thought we were), and many civs that start with Mysticism also have significant holes in their worker technologies to start. Teching through priesthood right from the get-go and putting off mining to tap that gold in your big fat cross(because hey, you know everything is in the BFC in this hypothetical start) might not be the most efficient way of going about it.
Founding an early religion is a good idea less often rather than more. After playing some games and getting accustomed to not grabbing that immediate shiny, one will better be able to understand the situations where early religion actually might be useful rather than a drag.
After all, Stonehenge and the Oracle are sub-par at protecting your Buddhist empire when your neighbor Hindu Isabella comes knocking on your door asking for a cup of sugar and maybe a city or 5.
