First off, you're right that hands banking primarily on the factor I labeled as (1) in my earlier post (we can call these "draws", though they don't have to be flush/straight draws in the traditional sense - sometimes hoping to improve can be a reason to call with unpaired hands even without a draw) are less affected. The most affected hands will be those on banking on (3), that you will not bet again.

If you always bluff the river after bluffing the turn, you are making one of two mistakes:

1. You are bluffing the river too much. This essentially gives implied odds to all your opponent's bluff catchers - they are now downright profitable rather than breakeven, as at equilibrium, and he can exploit by calling you with them more often. You lose money with all your bluffs. You recoup some of these losses with your value hands, but not enough to make up the difference.

2. You are not bluffing the turn enough. Here, the exploit is for your opponent to fold all their pure bluff catchers (those with little or no chance of improving on the river) on the turn. This costs you money when you have value hands, because you are not winning as much with them. It may also sometimes cost you the pot if it results in your opponent getting to see free cards and/or a showdown with a hand that would have folded to a turn bet.