Two electric 52-gal water heaters plumbed in series (cold water supply to one, then out to 2nd WH, then out to hot supply for house).

What puzzled me was that the incoming cold water supply was attached to the 'Hot" connection (on both water heaters), and the feeder line to the house was attached to the "Cold" labeled connection (IN) on the water heater. Ok, so sloppy installation, illiterate plumber or whatever. However, what got me wondering more was the fact the hot water temperature at the kitchen sink only measured at 105 degrees at hottest, despite the fact that the thermostat control settings on both water heaters was set to Hot (normal hot at top heating element), and Very Hot (at the bottom element). I do not carry an amp meter to verify current at the heating elements (though now I think maybe I should start).

My Question - Doesn't the 'Cold' connection feed through a dip tube to the bottom of a water heater for initial heating? Therefore, by my rudimentary understanding, by reversing the plumbing connections, 'hot' water for the house is being pulled from the bottom of the tanks (eg. hot water rises to the top of the tank, right?). Would reverse plumbing of the supply lines cause a low temperature reading?

Just to complicate the picture, water heater manufacture dates are 1993 & 1994, and this home is a log home in the mountains that was de-winterized a few days ago (but water heaters should have been in operation for at least 3 days).