The British male has an invincible compulsion to show a bit of leg, even though it is rarely appropriate, or fetching. Our climate, after all, doesn't often demand drastic lower ventilation; and the most common cut of leg is blobular thigh married to challenged calf, usually of a mortuary or mottled hue. The oft-accompanying socks, too, nod to the knotted handkerchief rather than the sportif (although they do at least cover up the feet).
So what is going on here? Why are there more and more men in shorts? Why do they now appear with the first primroses, and sometimes all year round? Well, there's the obvious influence of foreign holidays, but I think it's more to do with a hazy, inherited imperial hotchpotch of mad dogs, midday sun, gin slings and Carry On Up the Khyber: what you see might not be pretty, but it is a fine and jolly example of our famous sense of humour, both conscious and unconscious.