Anthrax, I'll try to find something for you later, however there have been at least too peer reviews that showed injesting a larger serving of soy caused a reduction in total blood serum testorone levels, and an increase in shbg levels in healthy men, within 2 to 3 hours of consumption. There is another one I've heard of showing after longterm injestion of soy, men showed elevated estragen levels. Granted the odds of finding a review over studies done on bodybuilders would be highly unlikely. Almost no one uses only bodybuilders for test subjects, even in nutrition and resistance training research. You know this. However, if an effect on hormone levels is caused in healthy young men, in research, it is very reasonable to assume a similar trend would occur in bodybuilders. Being in better condition does not offer any protection from altered hormone levels from on's diet.
Hope you don't do low rep sets then, if you always follow the lastest research, as it has been proven consistantly that 12-15 rep sets stimilate more neural activity and cause similar increases in testosterone levels, but a greter inscrease in hgh levels than doing lower rep sets in the 4-6 rep range. This has been shown in both untrained subjects and atheletes. It has also been shown that doing more than 4 sets is worthless in terms of hormone release other than cortizol (which is a negative not a positive). Funny how so many guys make gains on a 5X5. Just food for thought.