See, to me, you've crystallised exactly in these comments the difference between the best and being the greatest.Also, being an aberration is more to do with what others are capable of rather than what you yourself are. Warne and Murali's excellence at wristspin is unusual only because wristspin is incredibly difficult to bowl, not because they're better bowlers than some of the best seamers.
For me, greatness as a cricketer is purely, 100% related to your own skill and that of others is irrelevant.
One innings in which you consistently score twice as much as any other batsman really = two innings, IMO.Averages don't work that way, though, and you know it. No batsman can be two batsmen, because you can only bat one innings at a time. Batting and bowling, however, you do at different times of the game. So you really can be two players in one if you're an all-rounder of the highest class.