This I am aware of Tony, it was just an observation and comments I'd learnt from a tyre fitter as well as Michelin.
I was also advised that swapping tyres around these days is a waste of time, as the compounds are a lot different as in days of yore when we used to do it, because our fathers used to do it.
Mercedes and Michelin advise that new tyres should always be fitted on the front, as rear tyres are 'trailing' tyres and are not subject to the same wear and tear as front tyres which have to contend with a lot of movement when cornering and parking and get a lot of wear on the shoulders.
Incidentally I use nitrogen in my tyres rather than air, as it is not subject to temperature change like air, air temperature change inside the tyre can cause moisture which can effect the wire rim of the tyre where it meets the wheel. Costs about £1/£1.50 per tyre on the initial fill and subsequent checks and top ups, if any, are free of charge, takes about 15/20 minutes to discharge air, dry tyre internal and refill with nitrogen for all four tyres, as in most things don't mix n match.
I don't believe in skimping on tyres, never have, they are your first contact with the road, and I'm still a rapid progress motorist
Hey but do whatever floats your boat, I'm only passing on comments and info from people who do it for a living.

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