Did Derevenko ever say anything or write his own memoirs about the Imperial Family?
I don't think so, he may have possibly been illiterate.. ? Not sure about that.
THough I am very late in this discussion, I want to say that the legend of an illiterate Derevenko come from commissar Pankratov, who wrote he was "half-illiterate". But I think it has nothing to do with his hability to write or read, because he could at least write letters. There are some extracts of them on the Russian Wikipedia. By the way, one can think what he want of Wikipedia, but this page is very rich on balanced information:
http://ru.wikipedia.org/wiki/%D0%94%D0%B5%D1%80%D0%B5%D0%B2%D0%B5%D0%BD%D1%8C%D0%BA%D0%BE,_%D0%90%D0%BD%D0%B4%D1%80%D0%B5%D0%B9_%D0%95%D1%80%D0%B5%D0%BC%D0%B5%D0%B5%D0%B2%D0%B8%D1%87I am sure it would be very interesting for the forum if a kind member could translate this page for the English Wikipedia, or, at least, for the forum. There are answers to a lot of questions. Something I already post here and there in our pages.