I don't know if it should be blamed on/related to the mountain thing...He played and competed awfully even before that: against Kiefer in Cincinatti, for example: I don't remember having seen him play worse or be in a worse mood than in that match...he was not too sharp in Montreal or US Open either...I actually think that he played better (he hit a few impressive shots) against Karlovic this week that in Cincinatti or Montreal, only that he looked totally unmotivated and did not compete well: he gave away 2 service games and 2 break points - at times it looked as if he were playing an exhibition match, as if the result did not matter.
all in all, I think this is a good decision, hopefully he'll manage a comeback, but lets wait and see what happens next...
I'd like to add that he was already unhappy at Wimbledon. Let's not forget he decided to break up with Sasha, so there must have been some unhappiness already. I remember one of his interviews then. Back then I already thought he was down. I didn't know how far it would go.
In fact, I can now remember that in his Ferrero match in Hamburg he was asking Sasha if he could just retire and fans esp on TGFR have complained about his total lack of motivation. I think it's been a long time and he only hit rock bottom after the US Open and hasn't come up again.