There's an interesting anomaly that you people end up making in discussions that I have observed.
Roger's greatness is downplayed by many (most non-Fedfans) due to him winning 10 of his slams against non-Big 4. He won them against lesser players. So, let's give in to this point for once and consider him a pseudo great player, not really a Big 4 (that is a logical conclusion too, then).
For portraying the greatness of each of Djokovic, Nadal and Murray we keep saying that they played in the era of the Big 4 (we include Roger here). We might say that Nadal has had to face Roger in 9 slams en route to victory. "He had to beat the great Roger in 9 slams to win". Similar things can be said about Djokovic and Murray. We talk about Djokovic's victory over Roger and that he had had to overcome Federer in 2010-2011 and topple him in the rankings. He had to take away the HC supremacy from Roger. And then comes Murray who "lived in the era of the Big '4' and alongside Roger, so he is great".
To talk about the greatness of Djokovic-Nadal-Murray we use Roger as an instrument in the sense that beating Roger is greater than beating other greats. Something like this. But, we forget that we had downplayed Roger's greatness earlier in the weak era theory. So, how does he become an instrument to measure other elites' greatness?
And Roger really started to go down on HCs and GCs since 2010 Wimbly. That's a 29 year old Roger. So, beating a post-prime version of Roger who is a pseudo-great time and again probably isn't very credit-worthy. Here's taking away some kudos from Djokovic, Nadal and Murray each. This is the cost of the weak era theory.
Then we should believe that none of the Big 4 is really great by virtue of one theory or another (but a system of theories consistent with one another). And that the phrases like "Big 4" and "Golden Era" are farce. But, it's just not true. These 4 guys have been well above the field for a decade. To support what is obvious, the above theories have to be discarded, even the weak era theory from which other false conclusions may be wrongly done as seen above.