I don't understand your figures.
Are you saying at one stage, the Bank , lets say started off at $1000, managed to hit a LOW of $330?

I would find that hard to believe, and even worse, there would be massive bleeding in my bathroom if that were the case

What is your strike rate with your spreadsheet?
I'm working around a strike rate of Favourites which is 33% or so, maybe a little worse.

Edit : Just realized that you are probably betting to STARTING PRICES in the 3rd system, yet my idea is to bet to MY evaluated Prices.
So I could in fact have heaps on a 12 to 1 shot, rather than the 8% called for by the Public Market.