So corner to corner, town is about 11.2 miles. At a slow 12mph commute speed, you're looking at an hour to get all the way across town diagonally, hitting a few red lights along the way.

If this guy's normal commute is full corner cross town at 30mph he should be there in 25 minutes, taking lights into account. An extra 15 would be 40 minutes, or "stuck" following a 12mph rider for 3 full miles.
There's nowhere in those 3 miles to turn off and take a different route? OK, sure...