Mirth
I've flip flopped on this one. You shouldn't have to win away to your competition to win the league. Like you said, City didn't beat us at the Emirates to win the league.
However, it's City that has been dominating and it's about us, the challenger, who needed to make a statement by beating them, striking a deathly blow to their morale, taking 3 points off them and taking the title. That was easier said than done, as we could have been more attacking and got walloped like we did the season before. However, we absolutely needed to win. At the time, I didn't think so, but now it's become increasingly clear that was the case. Rodri's comments about our inability to win energising them and Neville's podcast really brought it home.
In 89, we beat Liverpool (who finished second) at Anfield.
In 91, we beat Liverpool (who finished second) at Anfield.
In 98, we beat United (who finished second) at Old Trafford.
In 02, we beat United (who finished second) at Old Trafford.
In 04, we beat Chelsea (who finished second) at Stamford Bridge.
I don't think it's all that relevant whether it's home or away, the more important point is that in a title run-in, the challengers will face each other, and the team that wins the game shifts the odds far greater in their favour to win the title. It's more than just the points, it's about landing a massive blow on their morale.