I remember reading about the concept of a blocking bet about 10 years ago, in a tournament context. Is this still considered a good idea, or just a half-assed way of owning yourself?

1/2 home game. Villain is loose passive, with laggish tendencies, VPIP/PFR of about 70/20. I am perceived as TAG. Hero has $440, Villain covers.

5 limpers, (UTG+1, MP, LJ, CO, BU) I make it $20 from the SB with JJ, folds around to villain in CO, who calls.

Flop ($43) 1069 I bet $35, villain calls

Turn ($113) 8 I check. Though I now have OESD with overpair, somehow I am leery of this board. Hits villain's range hard and I don't want to be raised off my equity. Villain bets $80, I call.

River ($273) 3 I have $300 left. I don't want to have to check-call a big bet. check folding seems weak. Is this a spot for a blocking bet, say around $100?

I wouldn’t. V has 87/98/76/t9/etc - just so many combos that beat you here and that doesn’t even include one-gappers. The flush didn’t come in so you may still be good, but I doubt it. Save your money.

Definitely checking

I honestly think blocker bets are not even worth considering implementing in your game. The times that they can be useful are so incredibly rare that it’s really not even worth thinking about. There are dozens and dozens of other concepts that will improve a players game more than blocker bets.

I can see a reason for making a small river bet if you think Villain will possibly call the bet with worse hands than yours that would otherwise check back the river. But that's not really a blocking bet, it's just a thin value bet. But you would need to be good more than 50% of the time that he calls, and I don't see what part of his range you think you're beating here.

I don't like the idea of betting with the intention to stop your opponent from bluffing. If you think your opponent is overbluffing the river you should check/call with all of your bluffcatchers (JJ-AA and Tx). If you think your opponent is underbluffing then just check/fold all your range.

What bluffs can your opponent even have here? Every conceivable hand he called on the flop has picked up at least a pair on the turn. He would have had to float flop with air, which seems unlikely. You said he's loose passive and then in the same sentence you say he has LAG tendencies. You seem confused on your reads. FWIW I don't think most 1/3 players would try to run an airball bluff on this river, so check/fold is probably best.

Does anyone think this is a good opportunity to check and balance out our OOP flop checking range? against this player x/c flop, x/r turn seems pretty viable. Thoughts?

i agree for the most part, but in low stake cash games it is surprisingly useful in my experience, but sizing is something need to be paid great attention to depending on villain tedancies. I see it working lots of the time but see people including myself misusing it and giving hand strength away.

I'm checking river. Ideally we get to showdown for free. Probably folding if he bets.

OTT, not a big fan of our passive x/call. I'd rather bet myself. Against a thinking player, I would consider x/shoving. We have 2 blockers to the nuts and he's going to have a very hard time calling without a 7 (and thinking players will fold some straights here). Force him to fold any 2-pair.

I’ll try to explain this concisely: it is extremely rare that you will make a blocking bet that either A)gets called by worse or b)folds out a better hand, which is the two reasons why we bet...a) for value and b) for bluffs and to fold out better hands.

Even worse, if you’re against a perceptive player, your blocker bets will be met with strong aggression (often with worse holdings than your own) and you will end up surrendering more $ than you would have if you just check/folded. Often you will induce bluffs that you cannot call.

Generally check/call or check/fold or bet/fold are much better, but don’t bet/fold with your bet intending to “block” a better hand. All that betting $100 does in your example is give your opponent $100 for an easy call with most of his holdings.

I could elaborate on this a lot more and might in the next couple days, I’m busy atm. But generally I don’t think blocker bets work well at all.

you dont beat so much here, unless he floated the flop

i think check folding is fine here, even against a lag

Blocking bets have a role particularly at low stakes. Many players don't have any real sense of the size of the big in relation to the pot. A $100 bet can look look "big" to many players since they don't have a clue as to how big the pot is. They aren't going to raise without a monster so you can easily fold if that happens. At the same time, they may decided to bet bigger with their TP to get you to fold your overcards (logic isn't of importance to these players, showing you they have a pair of big ones is).

against a loose passive you could use a 50$ blocking bet and your never going to get exploited. hes not gonna raise that unless he has a straight all sets n 2 pair will just call.

A loose passive player isn't betting the turn for 2/3 pot with a hand worse than JJ, so why would we want to put more money into this pot?