Yeah, keep in mind at athletics competition, a "false start" is deemed to be anything within 100m of the actual firing gun - because that is deemed to be below the level of human perception, and therefore someone "bet" or "guessed".
So I can't imagine a human can take a conscious step to get a FIVE millisecond advantage over another.
So I can't imagine a human can take a conscious step to get a FIVE millisecond advantage over another.