That's a bit of a twist on the original question. A better footballer would be, in layman terms, who would you pick first if you to build a team, your life depended on it, and you could only pick one at a time.
Think of two kids picking teams in a playground. This is obviously non scientific but it works and has worked for centuries across the globe. There is a pecking order, everyone involved more or less agrees with it and acts accordingly. You dont need any guy with an excel sheet looking up stats for you nor checking out any players' trophy count. It is in your best interest to learn that pecking order and to learn it fast.
I do agree that rugby is trickier, way trickier. Specialization is quite important in rugby. Push comes to shuv Dani Alves could play in any position. Nearly all positions share a certain skill set that is quite broad. Not so much in rugby. If you put Marler as a SH, FH or as a winger you'd be giving the opposition a huge advantage. That level of specialization makes comparisons more difficult.
Really?
Strictly speaking probably not, but you can by proxy, at least sometimes. You can, say, talk to people who have played with both, against both, coached both, coached teams against both. People who've reffed them.
And we have eyes too. I understand there a tons of grey areas. Actually most of it is grey. But there are white and black spots here and there.
