Joe

You and I seem to share a common interest in the unimportant:-) I had
an equally "nerdish" mate at University all those years ago. One
evening we were queuing for the cinema and he remarked that the
exterior light was flickering just like a "Cepheid variable" to which
I replied that we could "work out how far away it is then!"

Anyway, your query. I presume your figures of minutes of time per
degree are the rate of the HORIZONTAL component of the sun's apparent
motion rather than its motion along its path. Along its path, the sun
moves 360 degrees in 24 hours or 15 degs/hour or as you put it, 4.0
minutes of time per degree. Now in the summer, the sun moves
upwards during the morning at quite a steep angle (and moves downwards
in the afternoon similarly steeply). So the HORIZONTAL component of
its path will be less than in winter when the sun never climbs (or
descends) as steeply.

QED?

Jack