what you are saying is generally true, i generally present it in the same way, but you have to think about "able to be decoded right now"
an example of this is digital TV
yes it is digital, and it is super clear, but when a bird passes over or there is a storm or something you get a whole block of the screen section missing, some missed frames, etc... as in, a really bad situation can cause what seems to be like a quality issue, even though it is a complete non-transmission of information.
i have heard about long, twisted opticals giving problems... i cant imagine why it would be true though