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Every driver hears folk wisdom: half a tank saves fuel, coasting in neutral saves fuel, a sunroof makes a car less safe. New drivers take it seriously, but much of it is wrong. Let us clear up a few.
1. "95 octane is purer, burns longer and gives more power." Wrong.
Octane has nothing to do with purity or quality. Both 95 and 92 are blended from base stock plus additives; the difference is the octane rating and the knock resistance. Higher octane does not mean cleaner. Nor is it automatically more powerful: putting high-octane fuel in a car designed for lower octane burns incompletely, loses power and builds carbon. Use the grade the manufacturer specifies.
2. "Run-flat tyres cannot puncture." Wrong.
The real name is extended mobility tyre. They puncture like any other, but the thicker sidewall carries the car's weight after pressure loss, so you can continue at 80 km/h for 60 to 80 km. At the moment of failure they lose grip briefly like any tyre; hold the wheel, ease off the throttle, and the stiff sidewall helps the car settle. They do not prevent punctures, they just make one easier to control.
3. "Coasting in neutral saves fuel." Wrong.
Modern engine management cuts fuel on the overrun when in gear. Coasting in neutral uses fuel to idle and removes engine braking, which is unsafe.