On: How is NSA breaking so much crypto? (2015)

[whatshisface]

Possibly. If your rot13 takes longer to rotate a Z than it does and A, then it will leak your Zs through the AES. Similarly, you might accidentally write your own rot13 heartbleed.

[ENGNR → whatshisface]

So you just need to add an extra layer on another computer surely, or else I could MITM SSL by encrypting/unencrypting it