I agree that he's sort of pathetic, and definitely a laughingstock, but that doesn't mean that he's not capable of quarterbacking a team.
As for the first part, he's been talking about retiring for six years now, since 2003. It's been an annual ritual, and it gets worse every year. I don't blame him for wanting to play, but what's pathetic -- in my mind -- is the wishy-washiness. It's embarrassing to watch a grown a** man not be able to make his mind up. I understand him wanting to play, but this waffling is ridiculous. Can't remember any other player who's been as dramatic as Favre has the last few years.
And as for his ability, well, the Jets were 7-1 before his shoulder got hurt last season. That speaks volumes, considering they were a four win team the previous year. I don't necessarily contribute that all to Favre, same as I don't contribute the subsequent meltdown to him, but anyone who says he's washed up and can't play the position isn't paying attention.
With respects to Jordan, as damaging as his second comeback was to his legacy, he's still the best player ever. And he wasn't anywhere near as wishy-washy as Favre has been. When asked whether he was going to play a second year, he replied, very matter of factly: "I signed a two-year contract, and I'm going to play it out." Nothing like what Favre has done.