Terminology

 "Phantom double hit"

 From: Marty Storer Address: mlemws@yahoo.com Date: 10 May 2010 Subject: Realgammon role Forum: BGonline.org Forums

```The Phantom Double Hit is when your opponent already has a checker on the
bar and you hit a second one, while slotting within your board into a
simple or even a double shot.

It's common to hit loose twice in your board, but not so common to slot in
your board against two checkers on the bar, when you don't have to do so.
The usual situation when you do is to remedy some problem with flexibility.

This problem is from Praxis Volume 1: Match 1, Game 5, Position 7.

24  23  22  21  20  19      18  17  16  15  14  13
+---+---+---+---+---+---+---+---+---+---+---+---+---+
|         O       X   O |   |     O               X |
|         O           O |   |     O               X |
|                     O |   |                       |
|                       |   |                       |
|                       |   |                       |
|                       |   |                       |  X rolls 5-3
|                       | O |     X               O |
|                     X |   |     X               O |
|                     X |   |     X               O |
|         X           X |   |     X               O |
| O   O   X           X |   |     X           X   O |
+---+---+---+---+---+---+---+---+---+---+---+---+---+
1   2   3   4   5   6       7   8   9  10  11  12

"Snowie likes the very strange-looking 6/1*, 8/5, hitting a second checker
and keeping the midpoint, but leaving a double shot in the inner board.
Such a play, slotting in your board when your opponent has two on the bar,
might be called a Phantom Double Hit.  If Davis's checker on the bar were
on O'Laughlin's five point, O'Laughlin would hit twice in an instant.  At
it is, O'Laughlin can hit on the one point, putting two on the bar; after
that, slotting his five leaves only a single shot at the blot that really
matters. ... At a glance, the Phantom Double hit seems like a good try for
the 5 point."

In the analysis of the position, I mention another example, arising after
opening

3-2: 24/21, 13/11         4-4: 24/20(2), 8/4*(2)
6-6: fan                  Double to 2
Take                      6-1: ?

24  23  22  21  20  19      18  17  16  15  14  13
+---+---+---+---+---+---+---+---+---+---+---+---+---+
|                 X   O |   |     O           O   X |
|                 X   O |   |     O               X |
|                     O |   |     O               X |
|                     O |   |                     X |
|                     O |   |                     X |
|                       |   |                       |  X rolls 6-1
|                     X | O |                       |
|                     X |   |                     O |
|                     X |   |                     O |
|             X       X |   |                     O |
| O           X       X |   |     X               O |
+---+---+---+---+---+---+---+---+---+---+---+---+---+
1   2   3   4   5   6       7   8   9  10  11  12

I say that, after 20/14* with the 6, 6/5 is a strong alternative to 8/7,
which I still believe it is and which I'd play in practice today.

> I don't understand why the "phantom double hit" is called that. Does it
> just mean that when your opponent has two checkers on the bar, he has
> fewer shots than one might superficially think?

It's "phantom" only because you're not hitting two checkers at once, but
the end result is like a double hit. In other words, you make a play that's
like a double hit but isn't really a double hit.
```

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### Terminology

Alphabet soup  (Tom Keith, Apr 2004)
"Anchor and guard" position  (Chase+, Apr 2010)
"Back game"  (Marty Storer, Jan 2004)
"Baffle box"  (garyo+, Mar 2005)
"Bagai position"  (Timothy Chow, Dec 2012)
"Banana split"  (Rich Munitz+, June 2011)
"Banana split"  (Adam Stocks+, Sept 2004)
"Beavers"  (Sander van Rijnswou, May 1999)
"Beavers"  (Shuman Lloyd Lee, Aug 1991)
"Blunder", "whopper"  (Raccoon+, July 2005)
"Bot"  (Pit Bull+, Mar 2004)
"Bronstein" clock setting  (rew+, Sept 2012)
"Calcutta auction"  (Roland Scheicher+, Dec 2001)
"Chouette"  (Roland Scheicher+, Mar 2002)
"Cube provocation play"  (Chuck Bower+, Apr 2007)
"Dance"  (William R. Tallmadge, May 1998)
"Dropper"  (Robert D. Johnson, Sept 1996)
"Duplication" and "diversification"  (Simon Woodhead, Nov 1991)
"Equity"  (Gregg Cattanach, Aug 2000)
"Equity"  (Gary Wong, Dec 1998)
"Equity"  (Chuck Bower, Oct 1996)
"Equity"  (Michael J. Zehr, Mar 1996)
"Equity", "volatility", "claim", "market"  (Erik Gravgaard, June 1995)
"Freeroll"  (montygram, Nov 2005)
"Gammon price"  (Ron Karr, Aug 1996)
"Gammon rate", "gammon price"  (David Montgomery, June 1995)
"Gammon-go" (GG) and "gammon-save" (GS)  (Mary Hickey, Feb 2004)
"Gammon-go" (GG) and "gammon-save" (GS)  (Marty Storer, Oct 2002)
"Gammon-go" (GG)   (Chuck Bower, Jan 2004)
"Golden point"  (Daniel Murphy, Dec 2004)
"Holding game"  (Alan Webb+, Dec 1998)
"In the box"  (Ken Bame+, Sept 2012)
International phrase dictionary  (David Allen Sorensen, Sept 1997)
"Joker"  (Richard Divdesman, Sept 1998)
"Kamikaze play"  (Bill Patterson+, June 2011)
"Kauder paradox"  (Carl Tait+, Nov 1995)
"Latto paradox"  (Jean-Pierre Seiman+, July 2004)
"Lose your market"  (Shuman Lloyd Lee+, Aug 1991)
"MCV"  (Mislav Radica+, Oct 2009)
"PRaT"  (Raccoon+, Jan 2007)
"Phantom double hit"  (Marty Storer, May 2010)
"Polish prime"  (Jason Lee+, Jan 2006)
"Pure play"  (Daniel Murphy, Nov 2000)
"Pure play"  (Casey Forrest+, Feb 1996)
"Raccoon"  (Steven Keats, Feb 2011)
"Root number"  (Ken Bame, June 2004)
"Russian Bridges"  (leobueno+, Mar 2013)
"Short play"  (AJ+, July 2012)
"Speed board"  (Gregg Cattanach, June 2004)
"Splot"  (mamabear, Apr 2007)
"Squeeze", "trap play"  (Philippe Michel+, Feb 1997)
"Suicide play"  (Brian Sheppard, Aug 1997)
"Swing tournament"  (Carlo Melzi+, Mar 2006)
"Table stakes"  (Carlo Melzi, Sept 2002)
"Technical play"  (Adam Stocks+, July 2002)
"Thematic"  (Beauregard+, Aug 2009)
"Thorp count"  (Stephen Turner, June 1996)
"Time," "timing," "checker," "dancing"  (Marty Storer, Apr 1992)
Turkish names for rolls  (Lars Soezueer, Mar 1997)
"Vigorish"  (Anthony R Wuersch, Feb 1995)
"Volatility"  (Michael J. Zehr, June 1998)
"Wash"  (Hardy Hübener+, Sept 2004)
"Wash"  (Brian Sheppard, July 1997)
"Weaver"  (Alan Webb+, May 2000)
"Zone" of attack  (Matt Reklaitis+, Dec 2007)

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