Presumably old encryption/sign constructs used by pgp/gpg coupled with issues with serialization/de-serialization of data/cipher text?

you know what is worse than inferior cryptography? no cryptography. security is a human problem and people like me needs a well supported tool with lots of tutorial and plugins for almost every application and a manageable sets of quirks.

I agree that the illusion of security has drawbacks, but so does using too many tools that you don't properly understand.

Actually inferior (aka broken) cryptography is worse than no cryptography, because it makes you feel safe when you should at least know you aren't.