Not really. The odds of flopping a set or better with a pocket pair are 7.5-1. so ok 7.5 BB big deal. I've had my sets paid off in full more times than I can count and easily take pots that cover the measly 7.5 BB. Also the reverse can be true. You can be losing money with your raises to overcards on the flop when you don't hit. The advantage to limping with small/medium pairs in a cash game is the value of deception and more likely to get a big payoff. Whats the value of raising them? You say "hey I have some kinda pair or good cards" so if you come out strong when you hit your set then you're opponents are much more likely to put the pieces together and fold. Good job you got a couple extra blinds whoop-dee-doo-da. Good in a tournament/SnG but I don't prefer it in cash games. But whatever floats your boat.
flopping a set is 13%.
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Middle Pocket Pairs | Poker Strategy
When to raise with middle pairs before the flop
Most players make the mistake of automatically raising with middle pocket pairs, simply because they are middle pocket pairs. Raising with J-J or 10-10 before the flop should be reserved for situations where you are able to thin the field. These pocket pairs generally play well against one or two opponents. As soon as there are more than three opponents in the pot, middle pocket pairs are less likely to hold up without improvement.
Therefore, if you are in an early position and no one has called, you should go ahead and raise. Similarly, if you are in middle or late position and there is no more that one caller in the pot (aside from the big blind), you should raise and try to get it heads up or three handed.
If you are placed in a position where a reraise will almost certainly get it heads up, go ahead and reraise. However, if you reraise and more than two opponents call, be very careful after the flop.
In short, you raise for one purpose only: to thin the field. If your raise fails to thin the field, especially when you are in an early position, you should play very conservatively after the flop and be prepared to fold.
When to call with middle pairs before the flop
If a raise will not thin the field or there are more than two opponents in the pot already, simply call. Consider that calling with middle pocket pairs ends up being a terrific move when you flop a set in a multiway pot, because you have deception on your side and you're usually a very big favourite.
More to the point, with many players in the pot, your odds of success are significantly reduced. If you call and the flop contains overcards, you can fold cheaply. Many players raise and reraise with hands as weak as 8-8. Further, their preflop raising over-commits them to the pot and they will frequently bet or call on the flop when it is painfully obvious that they are behind. It would appear that they are hoping for a miracle 8 on the turn which rarely eventuates.
Many players would argue that you should raise before the flop in a late position with middle pocket pairs, even if two players have already entered the pot. There is some merit to that point of view. However, I find that a raise never knocks out the players who have already called. Since these preflop callers didn't raise themselves, my automatic presumption is that they hold reasonable hands, but want to see the flop cheaply. For example, if two preflop callers hold Q-10 and A-9 suited; and I hold 10-10, the preflop probabilities are as follows: Q-10 will win 25% of the time; As-9s will win 31% of the time; My 10-10 will win 44% of the time.
As such, my opponents will collectively win more often (56%) than I will (44%). If I raise in this situation, I am raising a pot that I will lose more often than I will win. Furthermore, if there are three opponents taking the flop, my chances of winning drop from 44% to around 33%, even if the third opponent holds two undercards to my pair. As such, call before the flop if it is multiway. Reserve your aggression for a favourable flop and fold cheaply on an unfavourable flop.
Also bear in mind that calling will hopefully keep the pot small. If you only call with 9-9 and an opponent has AJ, they may consider folding on a flop of 4-6-7 when you come out betting. Even if they don't fold on the flop, they will strongly consider folding on the turn without improvement. However, if you raise before the flop, this opponent may simply call you all the way to the river and try to "chase you down." Why? Because your preflop raise has inadvertently over-committed this opponent to the pot. You do not want any opponent to chase you all the way to the river with two overcards.
There is another great advantage in calling before the flop when there are two players already in the pot: you encourage opponents to obviously play their hands. If I call in the above three-handed situation and the flop comes A-6-3, the opponent holding As-9s will probably come out betting because there was no pre-flop raise. As such, they will immediately give their hand away and you can fold very cheaply. If you raise before the flop, the player is A-9 is likely to check to you on the flop and call if you bet. As a result, you will not get any information about the strength of his/her hand. Better to call before the flop and let your opponents give you the information you need.