I have been leaving a lot later for the last 3 weeks, encountered a lot more traffic. Plus weather conditions been a little crap wind etc. My times had been really hit 1.05 avg and speed down to mid 13's was getting a bit worried. Was putting it down to winter CX bike\weather\traffic then this morning clear run nice and warm (relatively) 55 mins and close to 16mph fastest time for ages and felt like a decent workout. Couldn't face doing traffic runs all the time would do my head in, hats off to you city commuters..
Will commute right up to Friday, even considering getting up early and going in to work Christmas Eve collect my run around work car and leave the bike out of the way @ work go back in and collect bike Monday ready for next week.