Re: Diplomacy rules question

From: jvverth@figaro.med.harvard.edu (Jim Van Verth)

Date: Mon, 24 Feb 1992 21:27:49 +0000

In article <1992Feb24.192245.3715@riacs.edu> nicholso@pioneer.arc.nasa.gov (Melvin H. Nicholson YBH) writes:
>In article <1992Feb24.183356.29583@gdr.bath.ac.uk> chpetk@uk.ac.bath.gdr (Toby Kelsey) writes:
>>
>> I have been only playing Diplomacy for a short time, and a
>>position has arisen which the rules are unclear about.
>>
>>Move:
>>(English) Fleet Norway -> Sweden
>>(German) Fleet Denmark s. Fl. Norway -> Sweden
>>(English) Fleet North Sea -> Norway
>>(English) Fleet Norwegian Sea s. Fl. North Sea -> Norway
>>(Russian) Army Finland -> Norway
>>(Russian) Fleet Sweden s. A. Finland -> Norway
>>(Russian) Fleet St. Petersburg (N. Coast) s. A. Finland -> Norway
>>[ s. = supports ]
>>
>>Obviously the attack on Sweden succeeds.
>[remainder deleted]>
>
>No.  The attack on Sweden fails.  [by overwhelming force at Norway]

No, sorry, it succeeds.  This is not a case of A going to B and B going
to A, this is A going to B and B supporting C to A.  The move Nwy-Swe
succeeds as it has force 2 and Swe has only force 1 (no one is
supporting poor Sweden), so Sweden is dislodged.  By rule X, if a
supporting unit is dislodged by an attack from *any* space (as Sweden
is), even one into which it is giving support (vis a vis Sweden), that
support is cut.  Therefore the Russian A Fin-Nwy loses the support
from Sweden, has only force 2, not 3, and is bounced by the equivalent
English F Nth-Nwy (supported by Nrg).

>>  Doesn't it also contradict the idea that moves are
>>simultaneous?  You now cannot decide which attacks work
>>after calculating support/cutting support, as whether
>>support exists may depend on whether an attack succeeds.

Having written a Diplomacy adjudicator, I can say that the action
really isn't simultaneous -- you first deal with broken supports, then
do dislodged supports (in the special case given above), then resolve
attacks.  Convoys screw the picture up somewhat, but using this
technique everything with the current rules appears resolvable.  I've
heard of one case of deadlock, but I'm not sure if that's with the
current rules or the old rules, and still that's only one case in many
many games...

-------
Jim Van Verth -- Mad Computer Scientist at Large
Internet:  jvverth@figaro.med.harvard.EDU
Disclaimer: Universities don't care what their employees think...
Quote: "God may not play dice, but sure shoots a mean game of pool."

References

Diplomacy rules question
chpetk@gdr.bath.ac.uk (Toby Kelsey)
Mon, 24 Feb 1992 18:33:56 +0000
Re: Diplomacy rules question
nicholso@pioneer.arc.nasa.gov (Melvin H. Nicholson YBH)
Mon, 24 Feb 1992 19:22:45 +0000