Does 15 games wipe out 9 seasons? No.
Going on a good 15 game run when we're out of the title race and there's less pressure means nothing, because the league is ultimately done and dusted between the top 2 clubs now. It's no good going on this sort of run now we're out the title race. For me to change my mind we would need to go on a run like this at the crucial point of a title race i.e. when we're still in for a shout. Now you could say 'well we could still win the title', which is technically true, but do you deep down in your heart think we will? Or even put up a fight for it? No.
Another thing that would weaken my stance would be beating a team managed by Mourinho, because that's something we haven't done before.
Having said that, top 4 and the FA cup would be a good season and it would lessen my anger towards him too, because football's all about winning trophies and 2 in 2 seasons would be great. That would mean I give him another season to see how things unfold next season.