"Mr. Joe Trader" might need some definition. For instance, I felt that HFT didn't change the game for "Mr. Joe Trader" as much as the rules limiting daytrading

"Mr. Joe Trader" might need some definition. For instance, I felt that HFT didn't change the game for "Mr. Joe Trader" as much as the rules limiting daytrading ($25k minimum for margin, restriction on round-trip trades per quarter) did. Now you need to be fairly well off or trade pretty much full-time to be able just to enter the game. Fees may be down but fewer players can play.