I heard JTL's old team manager at Endura on radio 5 live earlier. he stated that no way was JTL a doper (His words) he says the guy is pure class and couldn't or wouldn't do it. I really hope this is the facts, because if not it shines a huge light on Endura
On the brand maybe, but not other riders. None of them:
showed very dramatic improvement between 2011 & 12 as JTL did
won races well above the level they had won previously
saw a dramatic decline in their 2013 performances compared to 2011 or 2012
If there is some naughtiness it is difficult to establish when it may have begun. My recollection of 2011 is that he had a decent start to the season with Rapha
Condor Sharp (RCS), won an odd Premier but nothing consistently outstanding compared to many other riders in those races. Stepped up performance levels noticably in Aug/Sept with stage win and second overall at Leon and 5th overall and mountains jersey at Tour of Britain. Winter training then took place while still contracted to Rapha CS. Arrived at first Endura camp in January and blew the whole squad away on the climbs...which is why he went into Tour Med and Haut Var in Feb as team leader. Much stronger than guys he was not riding away from the previous Spring/Summer. Although these improvements were noted with some skepticism at the time, I believe it was attributed to things like greater commitment and training over winter, significant weight loss, longer /different types of climbs and an intention to peak for early races.
Although the rogue test may have been in Sept 2012 his significant physiological improvement came at least 9 months earlier.