I have to be honest, although I felt Martinez was the better fit for us (better passing and better command of his area), I was not sure whether he was on a lucky run of form or not but I still think we f*cked up massively by selling him to Villa. That is simply because I don't think it was an either or decision.
Leno was just coming back from injury, so it wasn't a crazy idea to ease him in especially given the fact his replacement had been outstanding in his absence. So you tell Martinez that you have 100% confidence in him and will be starting the season as the new nr. 1, get him to sign the contract and you'll evaluate in the coming months whether his performances were a fluke or not. If he keeps performing well, then you simply stick with him because even a blind man would tell he's a much better fit for us. However if they turned out to be fluke, you replace him with Leno and he has no leg to stand on if he complains because no player is ever guaranteed their place in the team throughout their contract, not even Messi is. You have to earn your place in the team, at least that's what all serious clubs demand.
You can tell those making these decisions for us aren't really serious about winning. Getting rid of competition promotes mediocrity, loads of players become complacent when they see they are competing with a bunch of jokers for a spot. Arteta and co f'ked up massively IMO.