Doing this every 200 hands would add a minimum of 0.75 big blinds per 100 hands to your winrate - more realistically it would be well over 1 big blind. That is

Doing this every 200 hands would add a minimum of 0.75 big blinds per 100 hands to your winrate - more realistically it would be well over 1 big blind. That is very significant in a tough game.