"He may be an enthusiatic (sic) amateur"
IT manager as it happens, though I'll admit the exact details of how computers do arithmetic is not my speciality but I don't see many network design, mail server, DNS server and so on questions on here.
Anyhow, my initial answer was off the cuff so to speak and I more meant that fractions don't fit well with using computers in the manner that everything is generally more orientated towards decimal on the user side of things, not the internal workings.