Ole literally had among the best records last season against top 6 (think it was 2nd to Pool), so the issue isn't that he can't beat top sides.
Even this season, if you look at the performances, 9 times out of 10, we win today, and we had enough good chances to beat Pool. Even against Chelsea, we had the better chances, although, I'd concede a draw was a fair result. City were way too cautious against us after what happened last year - and for me that is a sign of progress in a way.
Coming to whether Ole can lead us to title, the thing is no one knows. We're clearly improving and we haven't hit our peak yet. If we reach a point where we're going down or staying flat, I'd hold my hand up and say that Ole can't win the title, but that hasn't been the case. Let's first find what his peak is before just writing him off and taking another punt in the dark on a new manager, who'll tear the team apart to his needs, and may or may not be successful.