Counterfitted??

[soweak.]

Bet/Fold. Unless your opponent is regularly aggressive on the river. Aggressive players check/call.

A check/call line is too passive against typical neutral/passive players because you will get checked through too often and you will be missing bets with the best hand. Typical holdings on the river are:
1) busted flush draw.
2) middle pair that can both beat us and lose to us (99 and 55 asre examples)
3) a hand that ties us (anyone holding an 8)
4) Ax.

Typically, someone holding a lone Ace now has to worry about his kicker, and more than likely just call you down. You're realistically only going to be raised by hands containing a 6. Also you can get hands that have you beat or that you tie to lay down to a bet.

Question for SS gurus: When does a check-raise on the river against a aggressive player become standard?