Let's not get into a time machine and go back to arguing the meits of Martinez!
You can say his starting tactics against Japan were awful and he was lucky to get away with it - the goal that got them back in was a fluke and the counter for the winner came from Japan foolishly trying to directly put in a corner when they were so weak at set pieces. Or you can say his subs were spot on, their counter attack goal was excellent and turning that scoreline around and having a team that doesnt give up in those circumstances shows great skill. You could say against Brazil he was lucky with the OG, to avoid penalty and withstand so much late pressure or you could focus on the fact they beat the favourites and succesfully withstood so much pressure largely nulifying Brazils biggest threats. There is truth in both sides of that argument and you can look at it either way to fit what you already felt about him. The truth is he's prob not as good as his biggest admirers feel and not as bad as his biggest critic's believe. He is a mixed bag to say the least.
He's long gone, we had the good, the bad and the ugly for 4 years to shape our thoughts on him. No one is going to change their opinion on him now if you liked or disliked him as a manager back then you prob feel the same now so no point slipping into old arguments as no one is going to change anyone elses mind.