My 2 cents worth which is probably worth about that (2 cents) as I have only been betting for 42 years, but I still contend that you have to be prepared to lose at least 1 bank! E.G. AT THE PRESENT I have a plan that is showing 86% POT on total stakes BUT, without going into details is showing one maximum bank wiped out in the last 2 years and another that is looking VERY serious , in fact it all depends on 2 races next saturday!
BUT, even with 2 banks wiped out I am still showing a reasonable profit overall, puts a slightly different angle on things though, don't you think???