Sorry, but this is a very warped way of viewing things. It's not down to 'luck' that we won those games, it was because of efficiency in front of goal, taking our chances and the opposition either not being good enough to take their chances or because we were dogged enough in defence to snuff them out.
I do agree that it will be unsustainable to play like how we did tonight for the remaining 36 games because we're giving away possession too cheaply and gifting the opposition clear-cut chances. But the games you mention, like Liverpool (in both games), Wolves and Man City, each of these sides were (for the most part) unable to break us down. They may have had one or two opportunities where they felt they should have scored, but every team feels like that. It's purely hypothetical. Today was poor, but overall, Arteta has solidified our defence. That is indisputable.
We wouldn't have won any of these games 6 or 7 months earlier.
At the end of the day, if teams don't score, and we do, then that's not really our problem. Take your chances or suffer the consequences.