I just finished watching another Federer loss (this time against Murray at BNP Paribas Open, Indian Wells). New tournament each week, but the result is the same for Federer when he plays in one of them (and he's actually playing less and less each year). In fact, his loss to Murray is practically identical to his loss to Nadal at the Australian Open: At the end, he just gifted the match to his opponent, exposing his lack of confidence.
I am a big Federer fan, but I am definitely disappointed by his stubborness and arrogance. Indeed, his decision to jump from one tournament to another (and from one loss to another) without a coach, that other voice he needs so badly, showcases the "acquired" lack of humility after winning thirteen Grand Slams. With Federer's resume, it's only understandable to feel that "no tennis coach knows my game more than I do." It gets more difficult and requires great modesty to admit and accept the idea that even at this point in his career, he needs help.
He should just take the example of the one who succeeded in getting ahead of him. For 150+ weeks, Nadal was the number two tennis player. Even though he had a winning record against the Swiss, the Spaniard still had to figure out how to win on the big stage at surfaces other than clay. With the help of his uncle Tony Nadal, Rafa, the humble person that he is, managed to make the necessary changes in his game to "invade" Federer's turf. He not only won Wimbledon in 2008, but also the Australian Open two months ago.
Federer is probably not going to make drastic changes to his game, and in fact, he doesn't need to. That other person that he stubbornly refuses to let him join his inner circle can definitely infuse new tactics against the likes of Murray and Nadal and shake off that infuriating nonchalance he increasingly shows on the court.
The failure of his brief association with Darren Cahill was disappointing and worrisome. When will Federer win another big title is a mystery. How will the birth of a son/daughter in July affect his career will be interesting to say the least. Until then, my only wish is that somebody or something makes him see the obvious: He needs guidance.