Well, it's all speculation, isn't it? Who knows?

As for the claim that horses can be killed by it, I think that that could be true, but like everything else, it probably depends upon the continuity of use.

It would be time consuming, but interesting to study a given trainer's pattern of racing horses off layoffs. If they wanted to use a drug like EPO for a series of races and then discontinue it, for safety's sake, there would be some kind of pattern.

I admit that I only understand the basics about this drug, but why would it affect horses any more than it affects humans? All of those European bicycle racers used it for years until they got hammered, and they had side effects, but they didn't die.