These players you mention below, Eli, Flacco, Roethlisberger, at points in their careers, they played great. They played great enough to win multiple super bowls. The giants had one of the worse defenses in the league the last time Eli won the super bowl. He also had an average offensive line. So how was he able to still win? You will never win this debate, history "don't" lie.
What debate?? So you are basically saying that Eli would have two SB in Dallas??? I could argue all day that he would not, on the contrary I could argue all day that Romo could have two SB with the Giants and IMO you could not argue that he couldn´t.
In 2011 Eli had 16 interceptions, a QBR of 59.38 and their RB had 16 TD´s, just look at the numbers in the playoffs, without a running game and Defense there’s no way they win the SB. And just to be clear this is not a knock on Eli, he has performed well in clutch situations but to say he didn´t have much help like Brady or Rodgers is inaccurate at best, that was the initial discussion.
Basically I´m saying that if you are not a great QB you need a good team around you, I think Eli, Flacco and Roethlisberger would be the first ones to tell you that they don´t win it without the support of a godd D or good O line or Good running game.