Enchanting Books might give two incompatible enchantments

13w39a added the possibility to get two enchantments with one enchanting process on a book. This is a good feature, but you have the chance to get two completely incompatible enchantments, in my picture it is Fire Aspect II and Protection IV. Already saw Sharpness + Silk Touch and Fire Aspect + Punch.

This might be intended, but I doubt it.