I guess these things get done on a case by case basis. I'm not sure where I stand on this. Sure, a will should be respected. However, one does have some responsibility for those you bring into the world. Not easy.
This is interesting: http://www.thirdsector.co.uk/animal-charities-win-legacy-case-court-appeal/fundraising/article/1352773
And note that there are 'beginners' triathlons around (sorry, I have no idea how experienced you are in cycling and running so they might not be for you) that shouldn't be too testing and in which people turn up in all sorts of gear and with all sorts of bikes (I've marshalled on my own running club's beginners' tri, so I've seen all sorts of contraptions!).
I think all of this changes very little. Until or unless a Salazar athlete fails a drugs test (and I bet that will never happen), this will run and run and run until the day (which might never happen) that the anecdotal evidence become so overwhelming that it simply cannot be denied any longer - a la Armstrong. What should Mo do? I have no idea. I think the best course might be to leave Salazar with a carefully worded statement that exonerates the coach from any blame but pointing out that he needs to get out of the kitchen before the heat gets too much. A shame for him, but probably the best move in the long run. (Too many 'run' puns. Sorry)
And to those who say we're all getting too cynical, you can thank people like Richard Virenque and Lance Armstrong who denied it all for years and years and years and years until eventually they simply couldn't live the lie any more. Yes, I want to believe there are world-class athletes out there who don't dope, but even for the guys we like there will always be a small corner of doubt, especially when they start getting better.