OK so you correctly identified a blocking bet in a live 1-2 NL game? Good for you--now fold!
Ex: Guy has QQ on a T327K rainbow board. He bets $10 in to a $40 pot on the river and you raise it to $35 holding AQ high.
90% of the time in the 1-2 NL games they are going to tank, look exasperated and just say 'screw it--I call'
I have a friend who does stuff like this all the time. He is currently in a $2,000 down swing at 1-2 NL. Tourists in Vegas don't come out to fold! The 'move up to where they respect your raises' phrase has been thrown around a lot but there is truth to it. If you bluff someone who wont fold, its nobody's fault but your OWN.
The times this works out will feel great, gangsta and grand but it doesn't make up for the times it goes afoul.