I don't always carry puncture repair kit on the commute. My tanks have Marathons, I look were I'm going (try to watch out for glass and potholes), got repair stuff at work and I'm mostly never far from a train station or it's a short walk home/to work.
I can fit a new inner no problems in ordinary conditions, but no way I'll manage in freezing weather conditions. When it's cold I don't ride too far anyway.
On a longer, summer ride, I will carry the kitchen sink, don't have anybody to rescue me with a car!