Who are you trying to explain this to?
read what I posted, does it actually strike you as serious?
Jimmy Greaves didn't need to be able to run 11Km a game - he had a level of skill that transcended effort, and he would have thrived on modern pitches, and with the current regulatory standards for refereeing.
Underneath what I said, there is a serious point. the physical toll on players back then was greater than todays players because of the way the pitches sapped the life out of you, the physicality of the game was just as hard, but for more brutal reasons.
I am fully aware of the differences, I have watched it all happen before my eyes, not seen clips on you tube to understand what I'm talking about.
The underlying fact is, the ethos back then was to play your best 11 - in fact, if teams didn't in cup games they used to get fined for doing so. I could be wrong, but I believe Spurs were either the first or one of the earliest teams to be penalised for rotating their players.