I remember this thread coming up those 5 years ago, and it's good to see we're still debating it!

I recently had a nail repair done to a shoulder of a new Michelin. Done very nicely and you cannot notice the repair. It was a major repair and the tyre sent away to do it.

It was a pity, though, that it took so long to find a garage willing to send it away, and I was told repeatedly on the phone that the repair would be 'illegal'. Yes, if it was a standard plug repair done to BS AU 159 then it would be non-compliant to the standard and possibly illegal (though I don't know under what regulations/law you would be prosecuted [Construction & Use???]). But otherwise these repairs are fine and until Trading Standards and ASA start prosecuting garages for not telling customers the truth then we'll be stuck with this throw-away money grabbing situation which is no better than quick fitting garages telling customers their brake pads need replacing when there's 1/2" left on them.

Anyway, the tyre seems fine, well balanced, and no longer losing pressure. I would definitely do the same again.