In any modern society, there ought to be a higher proportion of royal/noble/wealthy bloodlines than would be expected based on the generational wealth and status sampling of the original historic population. What I'm trying to say is that there might be a higher ratio of royalty to peasent in today's genes than in the past. Why? Survivability. Anyone with money in the past was probably more likely to have access to nutrition than the common pauper. And while it is true that in any generation, there are far more poor-to-middle-class families than rich ones, the number of healthy children in wealthy families must have been a higher parent-to-offspring ratio than in poor families.
Even as I'm articulating this, I'm realizing the myriad of holes there are in the argument. Of course there are more "royals" today than yesterday - mathmatics demands it. Not to mention, the potency of so-called royal blood would be diluted amoung everyone, therefore making it as notable as a submissive gene for a mole on your left shoulder.
Sigh. Oh hell, I'll post it anyway.