In message , Colin Hammond
writes
Interesting correspondence. I always thought North South would be the best
to get early morning warmth and shield from too much heat in the middle of
the day.

I think the idea is in the summer it doesn't matter to much, and it is
easy enough to shade from excess sun.

I think the idea is that in the spring in particular, the sun is lower,
and the NS orientation make better use at this time of the available
sunlight.

But I suspect it is a fairly marginal thing.
--
Chris French