hey cccorlew,
+1 on only having to prove yourself to the one in the mirror. My lowest was -14F, Pittsburgh in 93-94. The trick to keeping toes warm is to use booties w/cycling socks(they're usually poly-pro), one pair of thick 100% wool crewe length(or longer) socks and a pair of shoes one size too big. This gives your toes room to move around. Been using this combo for years to great effect. A fleece headband in addition to a balaclava and/or hoody for your head. Wind/waterproof mittens and liners for your hands and you're set. Oh yeah, a bowl of oatmeal or a powerbar before leaving will help generate heat from digestion on real cold commutes...learned that trick from my grandmother. It works! Congrats on lowering your 'will ride' temp.