In a relegation fight I think Moyes is as good as it gets. That's why people are looking now and thinking he wasn't so bad. He was very organised and could get XI Sunday League players playing with enough structure and discipline to survive the drop.
However when you want the tactical mastery to go to the next level? Moyes is too pragmatic, too dour, too myopic. He will never achieve at that level. This is why when we were flying, we were laughing at him and now we're sinking, we're looking on envious.
In reality, Moyes isn't a bad manager nor is he a great one. He's a manager with some excellent qualities and some massive flaws, who suits one end of the table brilliantly and the other end poorly. If we want to move up a level, we shouldn't look back, the only question is whether or not Martinez is actually the man to take us forward.