Up to about 18 months ago when I was able to shoot in an old car factory - a number of old antique cars, I was very confident with exposure bracketing (5 frames +/-2ev, as wide as possible). Especially when coupled with the K5's wide dynamic range. I had used it a lot in a wide variety of situations. I pretty much knew what I was doing. I had my head handed to me. I had the run of the museum and shot about 50 cars. The big problem was the poor interior lighting against the very intense lighting coming through the old original windows from outside. Checking the shots as I went, did not prepare me for what post processing showed.
The windows were still all blown out. I should have shot two bracketed sets, one for the windows and one for the cars, and combined both of them together. With a single set of just 5 images, I was able to do reasonably well. The cars, with the interior lighting of the old building turned out pretty well - even with most of the cars being black in color. But those windows still haunt me.
The moral of the story here - is that there are extreme situations where a single frame of raw will not be sufficient. Bracketing is the solution in these cases. There are still other very extreme situations where even 5 frame bracketing at the maximum +/- 2 ev between shots will not provide the desired results. You need to recognize these and figure out an appropriate workaround (while shooting), using the tools and skills you have at your finger tips. It comes down to the photographer behind the camera.
You can do a lot of magic in post processing - but there are limits. It still comes down to the quality of the raw information the camera/lens captures.