Legs: to cover or not to cover

[Sweder]

I'm interested in legs.
That is, what people prefer to wear on them (or not) when running.
I know conditions play a part. For example, the weather is pretty cool (downright freezing today) and I would not consider running in anything but leggings.

Last year, as the weather improved around late Feb/ early March I switched to wearing shorts for my long runs - and I didn't like it. It's probably purely psychological, but the feeling I got was my legs, especially my calves, were ‘held together’ by my leggings. I certainly felt more discomfort barelegged.

I see that some top runners (including Paula Radcliffe) favour knee-length socks. Paula claims this helps increase blood flow in that area and reduces calf pain, and it seems to me my leggings may have the same effect.

I’d welcome any views on this, and any experiences that may support this view.