Isn't the best way to assess greatness is to evaluate how players performed againts one's peers. How they dominated their era and then try to project how they would perform in the modern era and with modern rules and conditions.
As Ian Chappell once said, the only rule is to assume that a champion in one era, would be one in any era.
I completely agree with that and Ian Chappell is not the only one who has said that. Over the entire history of the game almost all great players and students of the game have said the same and yet the fans wish to compare players of different eras.
This is a good time pass in a pub but to take it to the level of seriousness and passion with which people will debate how Grimmett couldn't have been any a match of warne, purely based on their interpretation of the stats of the two is amusing to put it mildly.
Of course we all love to imagine what would happen if Bradman had to face the West Indian pacers of the 70's and 80's or how Tendulkar might have played Lindwall and Miller but to understand that Tendulkar is a master batsman in his time and would therefore have been a master batsman in all times is the sensible conclusion to draw. But then the same conclusion needs to be drawn from Grace and Trumper through to Hobbs, Hammond, Sobers and so on.
Once we accept that bit then the discussion becomes a purely interesting one which need not become a source of heated argument.
Instead of running down players of the past by looking up stats on the net and drawing conclusions from it, modern fans would do so much better to take the trouble to read of the players of the past and ideally not accounts written half a century later. There are enough very good accounts available of almost all the great players of the game (in the case of the batsmen running into double figures in the number of books in some case) which make for lovely reading and help understanding the game and its history.
Unfortunately, it is not the favoured method of aquiring knowledge of the greats of the past for many including some of the modern cricketers.. That is a real tragedy.