What do you mean by "bind"?

I read a short piece on how prohormones are suposed to bind and convert itself to the real thing. Has anyone else heard of this?

Some prohormones are testosterone "precursors" and therefore are said to convert into testosterone once ingested. So I guess the answer to your question is yes. Whether this is efficient is another question all together.

I've been searching online but still can't find the answer to this question: at what rate and percentage does this convert. how many factors does this depend on....anyone?

For which compounds?