When I last wore my shorts and flipflops. we did a quick poll around a couple of sectors and the outcome was that I was probably "better presented" than 2/3rds of the ops room. It is all about perception, and personal opinion as West Coast says.
I love some of the comments these kinds of threads provoke. No one has said that there is more of a concern about attire than pay/pension/RP2/RP3 and it is quite easy to be focused on both at the same time. I've had the pleasure to be in the company of some of our European colleagues recently, have you seen what they wear in their workplace? Some of them are even managers, working in offices, WEARING JEANS
Even when visiting NATS HQ!!!
Really, who cares? As long as attire is not offensive, why should someone be forced to wear a particular style?