Iโm not sure how fragile your egg is but you might look at the actual city test cycle (
Dynamometer Drive Schedules | US EPA) to glean how gradual the acceleration & deceleration is. Given that such extreme type of driving will minimize turbo use and maximize battery charge, the epa city # makes sense.
Iโm still using the OEM tires on my โ58 and Iโve noticed meaningful mpg differences due to mild changes in air pressure. Iโm not surprised that a more aggressive tire will reduce achieved mpg.
The electric motor is between the engine & transmission. The trans fluid is the last to heat up. Iโm not surprised that the electric motor is not engaged for much of a winter morning commute. Again, lower mpg.
Lastly, reset your average mpg after each tank. A cumulative average isnโt helpful in giving feedback as you play with changes in driving style & conditions.
The 250 has more torque and better fuel efficiency than any prior Land Cruiser (except the 300). Hard for me to see that as anything other than impressive.