You could even follow the Unix model and do pretty well keeping the date and time (down to the second) in a single byte...
You are confusing bytes (8 bits) with words (32 bit or 64 bit depending on the system). A byte will only hold 256 discrete values so you could perhaps store the year in there but certainly not an entire date, let alone the time as well.
There was a time once when converting an integer value to and from ascii was prohibitively expensive (hard to imagine now), so it was not unheard of to store a year as 4 bytes.
I think what most people think with better control (at least what I believe, and I've heard others say) is you don't have to worry so much about what is in it. (ie not laced with something).
Correct. Coincidently, that's also why the pot in the Netherlands is of excellent quality: if they sell you garbage you would go back to complain (and you could even threaten to call the cops if you want to make a scene).
"Our reruns are better than theirs." -- Nick at Nite