Interesting thread, of late anyway. I started on page 5. These little bitty skinny bicycle tires on our Mirages are most helpful in snow and mud. So a Mirage would make a good winter car in the great white north.
A hundred years ago I learned P = F/A. Which is Pressure is equal to Force divided by Area. To increase pressure (on the surface between the tire and what it is touching), either increase the force (weight), or decrease the area (or both). The little skinny 165 tires certainly decrease the area. And with skinny tires, there is less snow and slush to be plowed out of the way (of the tire) as it is rolling along.
Case in point: Many northern guys choose a SRW (single rear wheel) 3/4 or 1 ton pickup instead of a dually, because the dually puts more tire contact to the ground and has less traction in slick stuff (sometimes a dually is absolutely needed though for the added security of high weight loads). And another case. I have 2 stinkin' kitty cats. 1 is of average size, if I'm laying on the couch and he walks across my stomach, everything is fine. The other kitty is a big fat blubber butt. If she walks across my stomach, her feet hurt like hell because she is so heavy on those little paws. She has "better traction" than the other normal sized kitty.
View my fuel log 2020 Mirage ES 1.2 manual: 42.1 mpg (US) ... 17.9 km/L ... 5.6 L/100 km ... 50.6 mpg (Imp)