They have performed very well, but it is not over yet for them. Arsenal is a good example for a team that destroys their own performance by dropping so hard. I didn't expect Arsenal to win every single game, but when somebody said that they wouldn't win for four games in a row, ...
Yes, indeed the struggle is not over, moreover, Newcastle's position is still not secure in the third place. There is still Man United who still have 1 game in hand while their pins are only 2 points different. Wouldn't it be quite interesting to see both of them?
If Arsenal are alone, they have lost their chance and fell to second place, replaced by Man City.
Newcastle position can still be taken by Manchester United if they win the remaining matches, but Newcastle has the chance to finish in the top four positions if he can win the next two matches, the number of points collected by Newcastle certainly cannot be chased by Liverpool. Manchester City could widen the gap with Arsenal if they win the one game they are still holding, Arsenal still have the chance to return to the top of the standings if Manchester City don't appear consistently in the next few matches.
If look at the performance that Manchester City has displayed so far and their struggle for first place, Arsenal chances of returning to the top of the standings are very small.