I used to live at a fractional address and it was pretty much impossible to represent your address accurately in a lot of systems.
I ended up usually writing it as "200h" instead of "200 1/2".
Worked surprisingly well. One of the advantages of having deliveries still carried out by actual people where the address apparently doesn't have to be an exact match.
Yes, I suppose as long as the street name is recognized it will usually go to the right carrier, at least for fairly short streets.
I used to work on postal address recognition software and I don't recall that we had any capability for recognizing strings of digits that contained fractions.
It was a long time ago now, but it seems like something I would have remembered.