HP (Yaku) Explanation – Flushes (1)
From: http://blog.jpmahjong.net/read.php/527.htm
In the last articles we discussed the conditions to make a flush hand, these following two articles will try to explain the vital points when making those hands.
Flexibility
After you get your starting hand, you have to consider the possible HP/yaku (mentanpin, half flush (hon itsu), kuitan (open tan yao) with 2 dora (lucky tiles), etc); that’s the habit most adept players must develop. Because if you plan ahead you can reduce your thinking time afterwards, and you can select more easily the best tile to discard.
When they recieve a starting hand with a few tiles in the same suit, beginners think of nothing but half flush, and erradicate completely all other small possibilities, this could influence the hand-winning percentage. Because at the beginning of the hand you only have 14 tiles ahead of you, and you have still 17 draws ahead of you, there’s a good chance things might change.
Here’s a concrete explanation of going for half flush:
The lucky tile (dora) is a random honor tile.
This is a real starting hand I have gotten, it was the South Round, therefore East is not a value tile (fan pai).
9 tiles in cracks (manzu), and it includes a 667799 shape. If we keep this hand concealed (menzen) it’s going to be hard to proceed. Therefore, in this hand a Half Flush is within scope.
But is a flush the only possible evolution for this hand? The answer is negative. If we draw 
or 
, we have the possibility for a conealed Peace Hand (pinfu).
If we only think about tile efficiency, here we would discard . But in this match I discarded , it’s very subtle, but it leaves the possibility open for Half Flush or Peace Hand at the same time. Beginners tend to rush to discard in this kind of hand, it may be arbitratry, but discarding so early on can make the other players feel uncomfortable and they’d begin being cautious about you, which is not a good thing.
The mahjong tiles don’t know what you want to draw.
“With this hand, I only need to draw a few more cracks and I’ll have a Half Flush!”
You see this kind of thing in many mahjong forums, many people believe this is the basis to go for Half Flush. In fact, speaking in all consciousness, when I say ”With this hand, I only need to draw three more 
, three more 
, three more 
, and I’ll have Big Three Dragons! (Dai San Gen)” it’s not any different.
The big problem in beginners is that they play what Japanese people like to call “e awase maajan” (e awase = “drawing pictures”; maajan = mahjong) — in your heart there is only room for one “ultimate final shape”, and you believe your hand will evolve just the way you want it to, what some people call “ideal shape” is something hard to imagine, it makes the hand lose all its flexibility for change.
In fact, mahjong tiles can’t now what you want to draw, and can’t adapt themselves to your desires. Drawn tiles are just a random occurrence. Even if we had an 80% chance of making a Half Flush, erasing the remaining 20% could be unfortunate.
When playing mahjong, every turn what you should ask yourself is not “what do I want to draw,” it should be “if I drew x, what should I do?”
Remember, you cannot control your future draws. What you must do, is make your strategy based on the tiles you draw afterwards, and not according to your ideal, but according to what is possibly benefitial.
Coming back to the example from a while ago, I discarded and the hand became:
After discarding 1p I had already planned inside of me for the rest possibilities:
a) Draw cracks or East Wind: Possibly discard , because at that point cracks and letter tiles (jihai) already offer enough possibilities for groups (mentsu).
b) Draw 
or 
: Discard . Because the possibility for a concealed Peace Hand is high, meaning the opportunity cost for the Half Flush becomes higher.
c) Draw 
: Discard . No new incomplete group (taatsu), maintaining the balance between Peace Hand and Half Flush.
Many beginners thing they just have to decide and plunge ahead with that plan, when in fact you must practice “formulating a future plan for the tiles you will draw.”
In this game my next draw was , even though Half Flush is only worth two Hand Points (han), in this situation it’s the easiest way to win; discard . As long as I don’t draw afterwards, the possibility for Half Flush is pretty big.
Later on I called pon on and , drew another and added it to form a quad (kan), and ended winning 3200 points.
In short, what I want everyone to remember from this article is:
1. Secondary tiles can be part of your final shape, under most situations there are many of these. It’s pretty important to give flexibility for the hand to develop especially in the first row of discards.
2. You must not blindly charge towards one direction to please your heart’s desire, you must adjust your strategy based on the tiles you will draw.
(to be continued)
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Comments from Garthe
The statement I would like everyone to revisit is the, “…if I only draw a few more cracks, I’ll have a half flush!”
Indeed, but if we only draw a COUPLE more different tiles, we’ll be ready with Peace and probably at least a shot at Double Run. In normal parlor rules, getting to ready fastest with the hand closed is generally a pretty good strategy because of the possibility of getting Ippatsu or Hidden Dora. More often than not, we’re better off going for tile efficiency than big points.
And also, don’t forget that Half Flushes lose value when not concealed. Without Dora or value tiles in this hand, its value is practically the same as a Reach+Peace hand anyway.
Finally, I’d like to consider one more way to play this hand. He didn’t say at what point he called the 7c but it sounds like it might have still been relatively early. With 4 pairs already in the hand, I would have probably tried to keep it closed and go for Half Flush+7 Pairs or Half Flush+3 Concealed Triples. Both hands will be at least mangan(8000 points) with a good possibility for haneman(12,000). From a tile efficiency standpoint, one could certainly argue against opening the hand here as he now needs 2 of a very specific 6 tiles to complete the hand. Closed, nearly any cracks move us closer to ready and even any letter tiles are potentially useful, especially Dora.
And I have more faith in my opponents clamming up with cracks and letter tiles once I’ve called for something. Even closed, it will still be pretty Pretty obvious I’m aiming for a flush, but many players will assume that I am not ready until I call for something. If I can get to ready and not Reach, I think I have a better chance of winning the hand as opponents will think they still have time to safely get rid of that dangerous tile.
For me, the possibility of those monster hands (or even baiman if I draw a couple Dora) is well worth the risk of losing the hand because I didn’t steal tiles.
