Indeed. That's why 'small increments' are key there: as you say, don't
significantly change content.
Blizzard have always followed this philosophy with their game balance changes: they make very small changes each patch. They are so careful that often, the effect they are trying to achieve won't be hit until after several patches. See, for example, druid effectiveness in Player-versus-Player: it's steadily, but very slowly, decreased since The Burning Crusade, as a result of druids being (perceived?) too good at surviving.
I mostly kept my Android game's existing content the same. The only changes I made were to slightly decrease difficulty each patch, as some areas were definitely too hard (the first boss could take up to 10 tries to kill, no matter what you did :).
One thing that users really love though is the release of a large chunk of content in one patch - e.g. a brand new area to explore. I don't think this translates well to websites or webapps - no matter how much of a killer 'feature', users can be very cynical or underwhelmed.
Finally, in enterprise software development, you need to be very careful with rapid release cycles as corporations are very dependent on the stability of your product, even if it's internal.
Horses for courses. The bottom line is to use the best strategy for the job.