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Camouflaged Ranges in the Small Blind

Camouflaged Ranges in the Small Blind

“No enterprise is more likely to succeed than one concealed from the enemy until it is ripe for execution.”
Niccolo Machiavelli

Whilst a lot of professional poker players pride themselves on their ‘hand-reading abilities’, they tend to assume that their own betting lines are hard for other players to read.

In actual fact, there are many situations in PLO where the majority of players have transparent ranges. With multiple streets left to play, transparent ranges Pre-flop do a great deal of damage to your win-rate.

When raising first in, camouflaging our ranges is usually a minor consideration. We seek to play the best hand possible and, since the alternative to raising is folding, we have only one playable range to consider. But sometimes we have two playable ranges to consider and that is when camouflage comes to the fore.

In this article we began to address the most complex opening scenario in PLO,

“What is the optimal pre-flop strategy in a 6-max game when the action is folded to us in the Small Blind?”

That analysis led us to the conclusion that we should use both a raising range and a limping range in this situation. Yet many of you will find, when you examine your database, that your limping range performs quite poorly.

The investigation that follows will show you a problem that arises when you construct a limping range purely out of hands, “not good enough to open raise.”

How a Capped Range Interacts with a High Card Flop

Let’s assume we want to play 60% of all starting hands from the Small Blind and distribute those hands between a limping range and a raising range. One of the worst ways to do this is to ‘split’ our range: raise the best hands and limp the weaker hands in a linear fashion.

And yet this is exactly how most players proceed!

If we choose to raise the top 35% of all starting hands and limp hands ranked between 36%-60% the limping range becomes weak on many high card textures. In the example below we use Pokerjuice to examine the flop interaction for a linearly split limping range on an AK♠2 flop:

 

Flop interaction for a 36%-60% pre-flop range

Flop interaction for a 36%-60% pre-flop range

Compare the flop interaction for this limping range with two alternative pre-flop constructions: a linear ‘raising range’ of 35% and an alternative limping range of 60% without a split:

Flop interaction for a 35% (L) and 60% (R) Pre-flop range

Flop interaction for a 35% (L) and 60% (R) Pre-flop range

Why Splitting your Pre-flop range is a Mistake

It is not surprising that the raising range hits this high-card board much harder, with 50% of the range interacting well with the board- twice the frequency of the 36%-60% limping range above. Almost 1/5th of the range is either a set or top two pair (Group A) and it is thus clear that a range so constructed can be aggressive on this texture.

However it will surprise you that diluting the pre-flop range by appending the weaker 36%-60% hands to the top 35% still leaves us with a defensible distribution post-flop. We have fully 5 times as many top two pair and sets in the complete 60% range as we do in the 36%-60% range. In fact the weakest range can only muster {2nd pair + a gutter} or better 1/4 of the time whereas the complete range manages this 38% of the time.

This pattern repeats itself on many high card textures whenever you compare a split range with a complete range. Since these textures occur with a high frequency (36% of all flops are unpaired and contain two cards ranked 9 or higher) it is essential that we build a limping range that can defend them.

Lesson: A limping range constructed using a ‘linear split’ is at the mercy of an opponent who can represent strong hands on boards which you cannot where he has three streets in position left to play.

Not only does he need not fear a check-raise from you on boards where your range is capped on the flop, but he can also represent high card run-outs which you cannot.

Pouring oil on the fire: The limp re-raise

Another problem we face when we retain both a raising range and a limping range in the Small Blind is that some players in the Big Blind will attack our limps, perceiving them as weak. As we saw in the previous article, an opponent who raises our limp 60% of the time makes us pay an average price of 1.7bb to see the flop whenever we do limp:

f(Raise) Average Price to See Flop
20% 0.9bb
30% 1.1bb
40% 1.3bb
50% 1.5bb
60% 1.7bb

 

Since we benefit from our opponent raising our limps less frequently we would like to modify our strategy to dissuade him from raising aggressively. One response that players experiment with is to start limp-raising with some strong hands. Unfortunately this action exacerbates the very problem we are attempting to solve. Why?

Because if after limping we raise when we have a strong hand our limp-call range is still very weak on precisely those boards which we need to protect our range!

Limp-raising discourages our opponent from raising our limp with a very high frequency but it does nothing for us when we play post-flop after limp-calling.

In fact what it usually achieves is a further range split, compounding our problems in the small blind by assigning some strong hands to limp-raising which would otherwise be in our open raising range. This enables our opponent to attack both our open-raising and our limping ranges more frequently!

No wonder so many players find it frustrating to play against aggressive players when they are in the Small Blind: they find themselves confronted by aggression at every turn.

Moving Beyond the Linear Split

I have shown conclusively that the simple linear split is an ineffective way to play our range from the Small Blind. Thus if we wish to retain both a raising range and a limping range then we have to find a better way of distributing our starting hands between the two ranges.

In my next article on this subject I will introduce the reader to weighted ranges. I will demonstrate that effective use of weighting leaves our pre-flop ranges opaque and reduces our opponent’s range advantage on high-card boards.

If you enjoyed this pre-flop analysis and would like access to the best theoretical work on Pre-flop play in Pot-Limit Omaha then you should check out POKER MATH 2020.

The first module of POKER MATH 2020, Pre-flop Principles is on pre-sale to my readers now; click here to read the syllabus and rave reviews of my work!

By | 2017-04-10T13:22:46+00:00 October 28th, 2016|

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