First off, I've never been a Rossi fan. Mainly because I find it very dull when the same person wins all the time. He is/was very good, he came over as funny and charming, although that has little to do with racing, but his popularity means he gets a factory seat in perpetuity and stops new riders showing what they can do, although with Ducati coming back a bit this isn't quite as bad as it was. I wasn't a fan, but I didn't hate him.
I wasn't a Marquez fan. He was great in 125s, but too aggressive in Moto2 and then too dominant in MotoGP. If there anything worse the same person winning every race, it's the same person getting every pole, every fastest lap and every circuit record as well.
What I think happened Phillip Island is that Marquez , as he said in parc ferme before an accusations were made, overcooked his tyre. On lap 14 he posted a 1.29.2, after that his laps times went up and down as he managed the damaged rubber, until the final lap when tyre life was no longer an issue. This makes perfect sense and fits that facts, including taking Lorenzo on the last lap, which Rossi is unable to explain. So what motivated Rossi's accusation at Sepang? Had he gone mad? I have a background in psychology and experience of dealing with people undergoing stress induced breakdowns, and I am far from sure. I don't think Rossi has had breakdown in the communally accepted sense, but he may have suffered a disruption of normal thinking. One of the things that commonly leads to breakdowns is the repetitive re-thinking of some event. What happened? Why did it happen? What could I have done differently? Normally this is just what we call stress, but major events and a few days of disturbed sleep while endlessly turning something over and over in the mind can start to affect brain chemistry, which disrupts sleep more and more makes a realistic resolution of issue progressively more unlikely. The obvious outcome from this process can be a full blown breakdown. I think after Phillip Island Rossi started dwelling on the fact that out of the "greatest four-way battle in MotoGP history" he came fourth. The first point of sports psychology is don't focus on loses, don't blame others, just focus on improving your own performance, but I think Rossi re-thought and re-thought that fourth place until he came up with the idea of being cheated. What I am not sure of is if he ever believed his own story, or if was only ever a tactic. If he was genuinely certain Marquez interfered with him and had evidence why not go to the FIM with it? Watch his face during the Sepang press conference when it's pointed out that Marquez took five points off Lorenzo. Rossi looks very strained when everyone laughs and then drops the idea, until he has another, more friendly audience of Italians when he tells his tale his great joy. That could be a sign of a real problem. It could be just stress and emotion and a need for a holiday.
OK, so was Marquez ....... with Rossi at Sepang? Undoubtedly yes. Did Rossi kick him, again undoubtedly yes. Who ......-up the most? Race direction. All competitors break the rules, that's why all sports have referees, umpires or what have you. The sportsmen break the rules, they get a penalty. Rossi should have been dragged in on the Thursday for calling another rider a cheat and liar. In any other sport that is calling the sport into disrepute. Rossi should have been told to prove it or got a stiff penalty and that would have been it, but race direction has no spine when it comes to Rossi, so we got a race that did a lot for internet usage and little for the sport. Again Rossi was clearly at fault. His fans may claim there was no kick, but there is ample video putting it beyond question. He should have been black-flagged and DQ'd from the next race. No arguments, no time to think up excuses, no "but it affects my championship". If you want to win the championship don't kick other riders. Marquez should have been penalised for his spoiling tactics. Maybe even the three points Rossi was given, as that carries no actual penalty, but I think two would have been more reasonable.
So all that said, I think Rossi has now done a huge amount of damage to the sport, and I'm not referring to the verbal attacks or the kick. Rossi somehow introduced the concept that anyone in front of him on the track is interfering with his championship; anyone who fights for their position against Rossi is helping Lorenzo, while anyone who doesn't fight Lorenzo is helping Lorenzo.
This concept has permeated through the journalists and commentators to the extent that when Ono was trying to keep his place in front of Kent in the Moto3 race at Valencia Nick Harris and Matthew Birt's comments were that Ono was interfering with Kent's championship, when the truth is that Ono was trying to achieve the highest position he could while Kent would still win the title without passing him but with one less point. Kent has even said as much since.
Racing is not interfering. Trying to be as far forward in the field as possible is the whole point of the contest and is the job or even duty of every rider.
Rossi's position is that because he leads the championship, he should be ushered through to the front. It's not clear at which point in the season this lack of competition for Rossi should start, half-way, two-thirds, but in Rossi's mind by the time the season reaches Australia, with 16% of the championship still to run, anyone who challenges him is behaving unfairly. This idea is so completely against the ethos of sport in general and all motorsport in particular as to be a mockery of competition. I think that this intimidation of other riders was the a major part of the motivation for Rossi's verbal attack on Marquez before Sepang, combined with a certain amount of jealously the ageing star feels for the rising one - what 36 year old sportsman wouldn't want to be 22 again and maybe something more unhealthy. It was a tactic that ultimately cost him the title he was trying to win with it because he chose the worst possible target.
Is there a conspiracy? Certainly Marquez has no reason to want to see Rossi win. Not only has Rossi called him a cheat and liar and kicked him off his bike during a race, but Rossi also stirred up his fans to the point they physically attacked Marquez's home and family. Rossi never even expressed concern or regret over that. If Marquez did try to stop Rossi winning who can blame him? It may not be fair, but no part of Rossi's behaviour since Phillip Island has been fair. Did Marquez "help" Lorenzo at Valencia. I think Marquez didn't attack because he didn't need to. Lorenzo was always going to be running as fast as he could over race distance, Marquez might have passed but wouldn't have been able to gap him, so he elected to sit behind the entire race, conserve his tyre as much as possible, not risk either of them DNFing and take the win at the end when Lorenzo had no reserves left. This is the same tactic Rossi has used countless times, and which would still have seen Rossi lose the title. This didn't happen because of Dani's late surge. If Marquez was guarding Lorenzo when Dani pushed Marc could have let him go and them sat in third while Lorenzo finished first or second to take the title. Instead his actions were of someone fighting to keep second place so he could make a move for first at the end.
The crux of Rossi’s Valencia argument is that because his Yamaha wasn’t faster than the Hondas then Lorenzo’s couldn’t be and the Hondas were sandbagging. Rossi was just slower than Lorenzo. Rossi’s fastest lap was nearly 0.5 seconds slower that Lorenzo. He just didn’t have the pace of the front three. Could he have won if hadn’t started from the back of the grid? Maybe, but he still only had the fourth fastest bike and he was at the back of the grid for reason. I think the truth is that Rossi lost the title on his own, there is no need for a conspiracy because Vale sabotaged his own championship. Losing is part of competition, the much greater part because for every winner there are many more who don't win. No one likes losing, but part of sport is accepting it.