The blueline (showdown winnings) represents the accumulated EV of all hands that reached showdown, reflecting the quality of value betting decisions, bluff-catching, and call-downs. A strong ascending blueline indicates the player arrives at showdown with consistently winning hands, suggesting good hero call decisions and solid value betting. A negative blueline may indicate poor calls, incorrect value bets, or simply that the player is correct to be more aggressive (high SPR, fold equity drives). The ideal combination is a slightly positive blueline and positive redline, resulting in a sustainable overall winrate.