I frequently go to secondary, just because I have a couple of 5 gallon fermenters and one 6 gallon, so this frees up the larger fermenter for a new batch. As Igilmore points out, while the particulates may not settle any faster in secondary, there is less trub in the bottom, so you're less likely to kick up a big cloud when you go to the bottling bucket.
It's not a big effect---I have found that with a few days of cold conditioning in primary, plus a medium to highly flocculant yeast, that the trub/yeast cake is tight enough that it is hard to disturb it. But it is a comforting bit of insurance. I really hate bottle sediment. However, I still don't secondary if the only purpose is to reduce trub. It's not as important as avoiding the additional small risk of infection.