I can remember in the late 90s when the tyre softening reared its head again and I think it was around then they brought in fitting a tyre at the meeting, someone would bring 14 tyres and the machine examiner would write the date on the tyre with a white marker pen and then the rider would fit his tyre, some would fit the tyre in the pits some would go to there van and fit it, not saying it happened but remember the saying “here is one I prepared earlier” with the correct date writ on comes from the van 10 mins later I think that died out in recent times as I never saw it in my mechanic days but I think the focus of the cheating changed from tyres to fuel and for a time silencers