I understood it the same way....and did not see his post as a complaint either...I was merely bringing to the table that these other variables tend to slip by what the onboard computer calculates, I calculates mine manually as well and pretty much find the same thing,not sure if it's a system glitch or it's designed to report slightly more inflated numbers to pacify customers.
As a perfect example, hit the reset button back to zero when you're driving in 6th gear @ say 100 km/hr...it will start adding up pretty quickly,BUT take your foot of the gas, and it will start to lower those numbers pretty fast....does that mean you're actually running on less fuel? not exactly....it's looking at air mass sensor, fuel pump pressure,fuel air mixture, cam position and timing and assuming a given number, or at least that's how I understand it!
2016 MKC, Reserve. White Platinum Met Tri-coat.
Leather ebony interior.
2.3L GTDI ecoboost.
6-speed select SHIFT auto trans.
20" premium painted Alum wheels.
Equipment Group 300A.
Silver rust protection.
Xzilon exterior paint protection.
Weather Tech front and rear liners ....the rest is ALL Lincoln.