It is significantly more than a hunch and slightly less than absolute certainty. I have known personally several elite coaches as well as at least a dozen Olympic medalist.
Drugs are part of the sport. A part of me really, really wishes it weren't so but they are. That said, I detest the cover-up more than I detest the sin of drugs.
It means that I am wealthy enough to hire a lawyer to insure that I the ticket is never enforced.
You might find, if we were having this discussion over a beer rather than a message board, that we have more in common than it seems. There are two levels of morality here: the use of PEDs and the lie to hide that use. I detest the latter more than the former. If PEDs are here to stay (and everyone I know on the elite level says they are), then let's be honest about it. Otherwise, let's get serious about cleaning up the sport. If you think we are serious, read Francis' work.