I've read on the internet that, although these cameras have fixed focus, the distance to which the lens' focus is set can be changed (of course provided that the lens is removed from the rotary turret).

Although the old guidelines reported on Jeff Bridges' website say that infinity will be surely in focus if the aperture is set at 5.6 or below, I seem unhappy with details at infinity on my pictures, so I wonder if it may be the case to have the focus set to infinity.

Did any of you actually modify the focus and set it to infinity? Did you see any improvement? Did you eventually regret the change, and why?