Originally Posted by
wolfchild
The speed difference and rolling resistence between 700x28 or 700x38 or 26x2.00 is irrelevant for commuting, it's so minor that majority of people wouldn't even notice it. Speed and rolling resistence may be important for racing but not for commuting.
I agree, it doesn't really matter so long as you arrive at work on time.
In my experience, my fastest commute times have been on 28mm tires. The next fastest were set on 23/25 followed by 32/35. My commute is all uphill then downhill then uphill so that might factor in the equation. YMMV