No, I do not kwow of anybody who was experimenting that strict and comprehensive as it would have to be done in order to get clear and stable results. And I know many good breeders who had the same problems, in fact nearly all (Walther Foersch, Willi Harveyi, Allan Brown, Horst Linke, Günter Kopic, Martin Hallmann, and others). No aquarist has a laboritory and the time to start seriously an experimental series on this.
But I know some scientists who have done research on the question of the development of sex in fishes and other animals who do not fix it in the moment of fertilization. But to my knowledge all they have found out is the relationship to those environmental factors, and not how to influence it quatitatively by experiment. I do not know of any rows of results indicating that e.g. such an increase/lowering of temperature results in such quatitative a change of the sex ratio. But I shall try to contact them and ask. One of them is a German colleague from Berlin; maybe he knows more.
But I doubt it. When he put forward his results in lecture I heared and in an article I read, he was concentrating on the necessity of humic substances für blackwater organisms. He proposed to use oak and beech leaves, but there was no statement on quantity. So I presume that all these findings are results of qualitative research and not of quantitative research. But I shall ask him.