That was the original idea behind that restriction. However, we have received some criticism about it and removed the 3 month statement requirement, as the MAM master still needs to deposit 5000 USD of their own money, we consider it good enough insurance against careless trading. Having their own money on the line (and a significant amount at that) should be a pretty good motivation to trade in their own and their investors' favour.
Regarding the parameters for choosing trader of the month - trader of the month has never been someone with a 300% profit from a 50 USD deposit, and never will be. We take many different things into account, one of them being the percentage of profit. Among others is money and risk management, diversification of their portfolio etc. Thank you for your remark about the selection procedure.