Per many years ago if I'm remembering correctly:
The RF tire became bigger because of the increased demands put on the RF tire for many reasons.
The very first explanation I remember for going to a bigger/wider RF tire was to help get rid of heat from the increased work the RF tire was now doing.
Weather or not it was the correct answer or maybe just the answer those in the know like Chris Gabehart, JWD, Pat Donaldson and maybe even Harrel back then wanted to give, could also be debated.
Cross also effects stagger.
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I think the real smart guys, not me, think about stagger as just another tool to be used to help use your right side tires properly. ...