Originally hot water was delivered from 2 places on the tank. 1 from the top, the usual place. Also, oddly, from a pipe coming off the *bottom* of the heater before the drain spigot. My guess is previous owner thought it would be easier to add new service to this location rather than trying to splice into the existing service to the tank. I had my plumber just go ahead and cut/splice this service pipe to a T junction at the top of the tank with the other service coming off the top. In effect this shortened the service originally coming off the bottom by ~ 5 feet max.
My house doesn't have a ready-hot water circulation system / pump (which I understand involves this kind of second connection to the heater bottom).
So, I'm at a loss as to why it should take longer for water to get hot @ shower. It is getting colder outside, but I live in San Francisco, so the temperature really hasn't changed *that* much to make me think it's the weather.
I suppose 1 explanation is thermostat on old was unreliable, heating hotter than that prescribed by recommended setting on dial. Any other ideas? The pipe splicing thing seems interesting too, though how that'd cause it is beside me.