Regardless of who has what agenda, for those that know about this illness, know the varying degrees at which it can be experienced. It was clear he was suffering from it that year. Injuries and illnesses are not something exclusive to non-elite athletes. Nadal has played with injuries, his knees have plagued him, even his back plagued him. Federer has suffered from mono, and back issues. Djokovic has had elbow issues, Murray hip and back issues...No one is immune to injuries and illnesses. The extent of them and how much someone recovers depends on the individual...for all the talk we hear about Nadal's knee problems, it was Wawrinka who had knee surgery. If we are excusing Nadal's knees injuries, for their varying degree of impact on him, then why not for an illness?
Players get injured and sick, it happens...I don't think you will find any top elite player who hasn't at some point suffered from something less than optimum health.