A SWOT is like making a photoshot from an organization. The more research, the more pixels. However, there is a moment that you've got enough pixels.
Don't analyse just for the sake of analyzing. So a SWOT is always a good step in analyses because "if you don't know where you are, any direction is good" ( read direction as Strategy).
So Swotting is a valuable tool for getting the right number of pixels and it gives you the possibility to make change scenario's as well.
Good tool, a base for formulating strategies and a proven tool for gap analysis.