when you start saying things like "tab = 3" and "last start =5" - IMHO you are just back fitting a lucky set of numbers which may never be repeated.
you may as well say
and " only barrier = 7, 10 and 11" or
"Richard Callender has 4 smokes between races 3 and 4"

as I read somewhere-
"The more complicated the rules , the less likely it will repeat itself ."
LOL

just my opinion.
good luck

Aussie.