Jon,
To be more specific, WHL claimed this was the cause of the vibration and hence were apparently not responsible for the cost of its subsequent fix - as you and I probably know, there were a myriad of reasons why the Lynx vibrated the way it did, and initially a lack of correct knowledge by the REME was undoubtedly a factor when this first became a maintenance problem. Whoever cracked the problem of correctly "shimmed" MRGBs deserved more than he probably got, when you think of the cost of all those endless track and vibe runs it saved.