6 Pick Bet Grouping

[bullockbefriending bard]

Your explanation is correct. It's important to realise that effectively
the input many thousands of single bets come out of a black box and it
is then necessary for me to merge them into the grouped format to make
things more manageable. Given an arbitrary bucket of single bets, it is
by no means obvious how they should be grouped without doing something
algorithmic. In grouping, it is also important to not inadvertently
introduce any new single bets.

For the purpose of this discussion, I am also assuming that all bets
are the same size. That's not the case, but can leave that little twist
for another day.