I'm neither clueless nor unthinking. I find it difficult to accept that the small additional side thrust encountered in the 5(ish) seconds that it takes to start the engine has a significantly higher effect than the side thrust encountered during normal running. Let's face it, it takes hardly any more time to start the car than to change gear - and you do that far more times than starting up.
By your reckoning my Series 2a Land Rover with 460,000 miles on the clock should be on its 7th clutch by now, whereas it's actually on its second. Likewise, all the Discovery's I've owned should have been on their 2nd or 3rd - but were still running originals at 150k+. Ditto the current Xantia with 170k+ on its original clutch.
BTW, the Xantia owners handbook says you should depress the clutch whilst staring the engine (petrol or diesel) in cold weather.