Not true at all. Rossi and Burgess were a development powerhouse. See 2001 on the NSR, 2002-2003 on the RC211v, the M1 as soon as he got on it. The 2005 being "the" best bike, Rossi says, out of all his Yamahas. When the factory he rides for, listens, they win together. Ducati never listened to them, Corse knew better, so they thought. We see how that turned out. When Rossi left the entire M1 program was spun around Lorenzo. And was until this year. JZ even stating that to get the most out of the bike you had to ride it like Lorenzo rode it. That finally changed this year when Yamaha changed the chassis, at Rossi's request. Now the weight distribution, chassis, all dialed. Problem is the engine (Crankshaft mass) and electronics. It's the opposite of what you say, and Rossi is the best development rider in the paddock, and they all know it. You should read Sir Alan Cathcart's reviews of all the GP bikes over the years. I was reading his take on all the GP bikes for a decade and a half. He always marveled at Rossi's bike, stating easiest to ride, best sorted, etc, etc. Anyone questioning Valentino's development skills should probably stick to their own profession. The current M1 woes, well Valentino started telling Yamaha there was a problem 18 months ago, and really got on their arses 13 months ago. Yamaha have done jack bone sheet to fix these issues which is why they are in their current predicament.
Yamaha has always sucked at this, but Rossi/Burgess would tell them what needed to be done and they'd make the corrections May/June every time and wins would come. This is the first time since Rossi has ridden for them, where they've refused the input, or I guess refused to do anything about it. The old man still has it, look at the stats this year. he's busting Mav and JZ's ass 3 ways to Sunday. And he's an old f'er.