If he seriously said that after Armstrong demonstrated perfectly the folly of the whereabouts rule having much effect on PEDs use then Djokovic isn't as smart as some would claim. A drunk teenager could see the hole in his reasoning there.
I'd like to think most players now know better, but I'm not going to presume the worst because a busy professional athlete doesn't spend his days reading tennis forums and conspiracy theory blogs, so is lagging a bit behind.
I say it's up to the ITF to make sure the players know and understand the facts.
Mind you, some people are never happy. After dedicating far too much time to discussing how the tennis world is in denial about the potential for a doping problem, those very same people see new conspiracies when the top players start asking for the better controls they supposedly want themselves.
Call me bonkers, but if players have heard about what happened with Armstrong, and they aren't totally stupid, they won't need a PR person to tell them it's a problem. Even if a PR person has suggested they may wish to speak out about it, this should be welcomed by anyone who genuinely wants to see better controls. The only reason to complain about any player speaking out is if you don't actually want progress in doping controls, and would prefer to keep the status quo where there is plenty of opportunity to make accusations of any player you don't like.
Anyway, I think the momentum is there now. It's inevitable that increased blood testing has to happen, and it's probably only a matter of time before the blood passports come in. It's being asked about at every press conference, so if a player doesn't know the issues yet, they're going to need to do their research.