Winston fired this volley in
:

Are you saying it took me three *months* to decide I needed
to shower longer? Doesn't sound reasonable to me.
If that effect were in play, I should not have seen any
savings in the first couple months because I would have started
using more hot water immediately.


No, but over a three month period (Say September 1 through December 1),
you might decide you need hotter showers to be comfortable, especially
since you'll change the house ac/heating pattern during that same period,
going from about 78F to about 65F (typical).

As the pp said, you turn down the water heater, then you increase the hot
water flow to make the same comfort level you're accustomed to. The
colder the room, the more likely you are to run the shower hotter.

LLoyd