Tiger's had a pretty bad decline, but he did still come back to have a great 2013 season (albeit without winning a major). If his body would have stopped betraying him, Tiger would probably still be a Top-10 player right now and probably won a few more majors, with a shot to catch Jack.
Nothing as precipitous as the drop-offs for guys like David Duval or Ian Baker-Finch who, while not being nearly at Tiger's level, were good, major championship-winning golfers that completely lost the ability to play the game anymore. I never cared much for Duval, as he usually came across as an ass during his heyday, but it was hard not to feel bad for him after he fell so far in such a short time. I was actually pulling for him when he made a run at winning the U.S. Open in '09, I believe.
Similar things happened in baseball to Steve Blass (who could no longer throw strikes, seemingly overnight) and to a lesser extent Barry Zito, though in Zito's case he eventually got things straight and won a World Series. But he was never the same pitcher in SF that he was in Oakland.