In many cases, this is a case of trial and error. Take clothing for example. Now I have it from Kristoff's blog, that if it rains for 5 minutes, your going to get wet so you might as well keep going. I'd be interested to see who wears what in the pouring wet, but this morning in temperatures hovering around 8 deg and with persistent light rain, I ditched the waterproof leggings and let the warmth of the working muscles keep me dry...ish.
As an experiment it was interesting. I didn't get cold and apart from wet feet, scootered around my local lumpy 30 in a little over 1 hour 40. Not far from where I was last year, so pleasing to know that I'm not starting completely from scratch.
173.8 miles since Dec 30th