Do you have any evidence of this? I know Bridgestone initially refused, but do you have evidence that Dorna forced them?
Do you have evidence of this? Who was this younger rider?
All the top riders got the SNS - Biaggi, Sete, Hayden, etc
So only the drawing of pro-Rossi inferences, or the drawing of inferences by him, are valid?
Those in the pro-Rossi camp seem to have very different standards of proof depending on circumstances and influenced by their own allegiance themselves.
I am on record on the SNS tire era as agreeing with J4rn0's view that Rossi only got the advantages other top riders before him such as Doohan accrued as a result of his and their pre-eminent status. I don't think it requires much in the way of conspiracy theorising to suggest he had a major influence on the characteristics of the SNS tire that was actually produced each time though, which were not 6 different tires as I understand it, as Colin Edwards who might be in a position to know has actually said, although I do recall talk that he was unhappy towards the end of the era that Honda were having too much influence on Michelin and the SNS tires were starting to favor HRC, although not in that race Toni Elias won in 2006 it would seem.
As I said in the post you just 'liked', one would think Max Biaggi, not unkown for complaining, might have had more to say if the SNS tires were 'fixed', but the tires may largely have suited him as well as JPS said immediately after that post, and even Max might have had enough discretion not to want to offend Michelin who have a record of intolerance of complaint by riders whom they supply cf Wayne Rainey as Birdman can detail. In any case he won the first 5 titles, and the 2 subsequent titles because he was the best rider those years; it was complaint from his fans in regard to rival riders having 'advantages' with which I took issue.
I believe it is basically impossible to produce a tire that will make a 38 year old rider win a world championship against current opposition, or to produce a tire which benefits him and no-one else, which is why I don't go for full-on conspiracy theories in that regard. I have very little doubt that Dorna have manipulated the tires over the years to the disadvantage of less popular/unpopular rivals of Rossi however. Btw, you acknowledge but then seemingly dismiss (? why exactly) that Bridgestone wished to continue with the status quo in 2008/2009, and I would be interested to see your evidence that Honda, Yamaha and Ducati, or Michelin and Bridgestone themselves, who would seem to have been the major interested parties, wanted a control tyre rule.
Bottom line is that Dorna's focus is still much more on a 38 year old rider who hasn't won a title since 2009 than anyone else, however, and I believe anyone totally naive to GP bike racing who watched the Dorna coverage led by one Nick Harris wouldn't have much trouble drawing that inference. That rider raised with impunity (pretty much with Carmelo's tacit support imo) a wild conspiracy theory, it would appear to their irretrievable detriment, against two riders who are in all likelihood top 10 riders all time themselves, including the ludicrous proposition that one of those riders tanked a race he actually won. I haven't seen much in the way of complaint in regard to him having no evidence from Rossi partisans, and in fact those riders continue to be derided/booed etc by said partisans. As I have said, and Povol similarly, it is the events of 2015 which have led me to a personal dislike of Rossi, rather than just of an element among his fans as was previously the case.