I don't commute on a road bike but I could. I commute 5day/wk all year round (120F thru 25F) with rare rain but sometimes very heavy. 8.5mi each way.

I as have a shower/locker I only need to carry laptop and change of clothes to work, so I carry everything on my back.

The bikes I use are a Jamis Sputnik FG or a Lemond Poprad with nothing attached I wouldn't have on a road ride. Lock up has security cam on work campus and is better than being on the street, however there have been waves of bikes stolen, mainly those which were poorly locked.

25c tires, relatively good roads.

Al