Actually Sanz, captaincy is not just about tactical ability. Sachin has always had a good cricketing brain. If you had noticed, even during Sourav's reign, Sachin will always come up and offer his bit of tactical advice, almost all the time. It was his man management and spotting of talented cricketers that was the problem, alongside his inability to handle all the politics of being a captain. This is not something new. I have always believed he was like an unofficial vice captain in the side. He came up with the idea of him bowling around the wicket to squeeze the runs against Pak etc. Obviously there are days when his tactics or ideas don't work, like in the last game when he gave his inputs and they obviously didn't work.
You are right in one respect. Most of the guys in the media are making it seem as though everything Sachin does works. That obviously is not true. And the media are also making it seem as though this is the first time Sachin is offering his tactical inputs. He has always done that, when India have won and when India have lost. But the point is, when he is not in the side, it is a big loss. He brings a lot more to the side than just runs and (occasional) wickets. He has a good tactical brain and can offer some new ideas to the captain, can cheer up the youngsters by talking to them (as you said, he is the GOD of Indian cricket and so many guys get motivated just because of him talking to them). You cannot disregard all that. Yes, he can improve on his play in the big matches, but CHOKER is too big a term. It is not like the knock out games are the only ones that have pressure.