== Why is that questionable? == 

 Saying that something is the most common in history presumes that someone has made a review of history and compared the frequency of different things. If someone has done so then we can report their findings. Absent any such study it appears to be a mere conjecture, no different from saying that something is the most loved or hated. If it's verifiable then let's verify it. If it isn't, then we should remove it. -