I love wearing shorts in the Summer but it is often hard to feel "dressed" wearing shorts while maintaining the casual feel that you want from shorts.
Working shorts (especially the dressier wool shorts I've been seeing a lot lately) back to a cardigan seems like a great solution. At least everytime time i see it done it usually looks really good.
For me this Summer I'm wearing a lot of shorts with super-lightweight, unlined jackets.
They work even better for me because they fit a little looser and when I am out shooting all day I have more to carry (extra battery , CF cards etc) than I can carry in a cardigan.
I have recently bought jackets from Engineered Garments, Junya Watanabe, and 45 RPM. I find I'm having an Italian Winter and a Japanese Summer.
I will have to do a separate post on these jackets soon, maybe during Pitti when I am really putting them to the test.