I think his point was the same as mine: If one is perfectly normal, then one has virtually no chance of ever being an Olympic or professional athlete. A perfectly baseline normal person simply has no possibility of training up to that level, no matter how dedicated. Ergo every separation and red line (arguably except for sex, but that's being degraded because even absent medical intervention, humans are remarkably diverse) must needs be artificially imposed.
Doesn't mean that mandating some maximum acceptable level of hormones is necessarily impractical, evil or morally wrong, it just means that we should recognize that it's arbitrary and therefore proceed with caution and humility. Sarah Robles and Cheryl Haworth are also far outside the norm for women, yet no one argues that they are not women. To be Olympic weightlifters, they have to be; that's the required starting point, then the requisite incredible dedication kicks in. Semenya is clearly much farther outside the female norm, but where we draw that line needs very careful thought. For someone like Semenya, this might (or might not) be taking away the only bright spot in her life. I'm not so touchy-feely as to say that prohibits drawing a line on qualification, but surely it should not be a knee-jerk thing based on a natural condition. I'm all for prohibiting competition for transwomen or those who have otherwise medically transformed themselves, but when it's G-d or nature, I'm a bit more cautious.
It might take away her bright spot, but that is the cruel nature of life. Some people are born with a defect that kills them before they reach the age of 10.
The only reason Semenya is winning anything, is because she has the parts of a "he" and is competing in a class of "shes". She is in a sport where others are born with the parts in the right place. At best, there is an argument for something between male and female. Sucks, but she genetically is unlucky in most ways. The only thing she has is competing against women who were born clearly women.
