Applying this simple principle can have a dramatic effect (and subsequent improvement on your game). It seems simple, but this rule actually goes to the very heart of tight/aggressive play. Living by this rule forces you to question your choice of playing hands. The result will be a tightening in your starting hand requirements while simultaneously harnessing your aggressiveness into hands with the most likelihood of success.
Limping is a sign of weakness. Weakness is bad, unless you are trying to look weak. Trapping aside, let's look at why we shouldn't limp when we are the first to act and how the application of this rule can be the centerpiece of a good overall playing style.
Limping typically means the player has a hand they want to play, but they do not like it enough to bet. By limping they are trying to sneak by cheaply and hope they make something on the flop. This might work against passive players, but against good players it will cost you. More often than not, you will be punished for limping by a raise from a late position player and then you risk getting drawn into a costly hand that you probably never should have been involved with in the first place.
This brings me to the underlying principle of the rule: If the hand is not worth betting when you are the first to act, then it is simply not worth playing at all.
Example: You are in early position with J-10 off suit. You may be tempted to limp with the hand, but would you normally raise with it? Probably not. Why? Because you are put of position to play such a hand.
If you take limping when first to act out of the equation, you end up playing better hands. Obviously, position plays a key role in this. If you find yourself in late position or on the button and are the first to act, many more hands are worth betting than when you are first to act under the gun. Thus, this rule reinforces the importance of position in determining starting hand requirements.
Aggression, however, is where this rule really pays off. By betting when you are the first to act, rather than limping, you take control of the momentum of the hand. Never underestimate the power of the big "mo" in NLHE.
By raising whenever you are first to act, you will thin the field. Because you are only betting hands worth betting, you have a better chance to make a winning hand against the few callers than if you were merely limping with a sub-par hand.
Most importantly, you will take more uncontested pots. If you have not realized this yet, trust me, it is better to take 10 small uncontested pots than to take one large contested one. The only way to take an uncontested pot, by limping into it, is for it to get checked around 4 times.
If you have not yet taken this rule to heart, try it. Play a few tournaments applying the rule. If you are unsuccessful, I will wager that it is your starting hands rather than the rule that needs adjustment.
To put it simply, limping when first to act is a leak in many games. Most do not notice it because they are only losing a small bet each time they are re-raised or where the flop misses. Plugging this leak is a key first step in developing a tight aggressive playing style. It will force you to consider your playing hand selection and position more carefully, and where you find yourself the first to enter pots, doing so from a position of strength will result in more uncontested wins and a greater chance of success in contested pots.
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