Sometimes it isn't a bad thing to have a few miles put on the clock IF THE CIRCUMSTANCES WARRANT IT.

@ a Ford Dealer my father used to run, a young(ish) lad had an RS3100 Capri from new, abused it all the time. Every so often (3-4 months) it would come back for another engine under warranty .

After the 3rd engine, my father told the service manager to take it with him on holiday from London to Cornwall that weekend (long bank holiday weekend). Service manager ran it in gently for about 700 miles or so.

Handed it back to the lad on the Tuesday morning after telling him what they had done, lad never came for another engine again, yet he always used to come in for his services and never complained once.

As I say though, it does need to be warranted.