[anserin]

Since you're not increasing the number of variables, it seems to me that the problem of finding the initial Boolean formula (or an even simpler version of it) is fairly straightforward. Have you done any tests along these lines?

[nicolodev]

Yeah, even LLVM is able to decode part of the obfuscated expression. Sometimes, it fails greatly printing out the obfuscated expression. There're several papers available and I'll write about it.