:P

There are no rules.

Given territory A, B, C, and D.

Give nation 1 and 2.

Nation 1 controls A and B
Nation 2 controls C and D

Ok. A attack C with the support of B. Normally this would push him out.

But. What if C attacks B? Is the support for the attack cut? No, right? That's what I think I remember. But let me continue.

What if C attacks B with the SUPPORT of D?

What then? Logic would say that C gets to move into B and then A will move to C unsupported since it is now vacant. Alright, but... one last problem.

What if Nation 3 orders his territory E to support hold B? So now, C cannot displace B, but is B's support cut? Is C pushed out?

Sorry, if you don't understand it I'll look for an example on the map that works.

If C has support from D then C->B and A->C as it is then empty
If C has no support, then C->B fails as you can't break support against yourself, and A->C with support from B
If E supports B then C doesn't move. As C can't break support on itself A->C
--
I think that makes sense...

So... even though in that last scenario C has outside support, it gets pushed out? A moves to C?

Alright that seems odd but thanks. Are you sure?

What did you mean then, I may have misunderstood. I thought B had the outside support. In these situations it's easiest to start by working out what C does, and then, based on this, you can easily work out what A does.
In all of those ones A->C though

When C attacks B (which is supporting the A->C move)
When C attack B with the support of D, but B is being support held by E, an outside army. All this is going on and A still has the command to move in on C.

It seems that perhaps the support B was supposed to give to A would be cut in all that madness. But perhaps not.

Okay, you know how you can't cut support against yourself?

In general, that holds, unless you DISLODGE the unit that's supporting.

Now, if E supports B's hold, then assuming nothing else, that unit is not dislodged, so we go back to the default case of the rule-- support is NOT cut because you can't cut support against yourself.

If it was the other unit, D, that moved, with C's support, then A would cut C's support, and D would cut B's, and nobody moves. And if D moved to A, with support, both A and C would be trying to cut support against themselves, and fail, and it would be a 2v2 move, which fails for both.

Does that make sense?

C can never cut B's support. It's a primary rule that a unit being attacked cannot cut the support to an attacker. D would have to do the attack to cut the support. Period. No exceptions.

Oh no Katsarephat, this is two different countries. It's not against myself. A and B are under my control, and C and D are under another's control.

But thank you I think I remember/understand now... lol don't know how that slipped my mind.

When did I assume it was against yourself?

And Draugnar, I'm sorry, but you're wrong. How can anyone give any kind of support if they're too busy being overpowered and forced to retreat? It just does not make sense!

Oh, right, "support against yourself"-- I meant the unit trying to cut support can't cut support if the attack in question is directed against the same unit trying to cut support.

I'm repeating from the rules. A unit can never sut support in an attack on itself. Period. I'm not worng. It's a fact. The adjudicator tests even validate for this one, I believe. Unless E gets involved in the attacks, you are describing a two on two stalemate.

You haven't actually read the tests, have you?

6.D.15 is the one in which you can't cut support for an attack directed against the would-be cutter of support. We've been in agreement on that one. But scroll a little further down and check out 6.D.17, would you? Dislodgement does cut supports, even when the move is directed against the would-be support cutter. And 6.D.18 is a corollary-- if the supporting unit survives, it still gives support in the same case.

Let's be reasonable here. Why would it be that a dislodged unit could still give support? It just doesn't make any sense. And the adjudicator rules agree with me here. And I bet if you read the Diplomacy rules a bit more closely, you would see an exception for if the support that the defender is trying to cut happens to be successfully dislodged, then the support is still cut.

Sorry, but them's the breaks.

So... what if the support gets attacked by an army with support, but it has its own support and is not dislodged? Does the orginal move go through with the support?
Do you guys actually understand my question?

@ Draugnar, you have overlooked this rule: From the Avalon-Hill 2000 rulebook. "Support is cut if the unit giving support is dislodged. If a unit ordered to support another unit is dislodged by an attack from any province (including the province into which it is giving support) then the support is "cut". The unit that was to receive support does not receive it."
@ Thucydides, I think figlesquidge understood your first questions and answered correctly. Your very last scenario isn't clear though. If you still want it answered I think you need to write down the list of moves you were thinking of.
In this discussion the above the word "yourself" is a little vague and may be the cause of misunderstanding. It could mean the same unit, or it could mean the same player's unit. There are different rules that apply in the two situations.

Thucydides: As per DATC 6.D.18, the support move still survives in that case, because it just goes back to a defending unit not being able to cut support directed at the same unit.

Yes, I understood.Hopefully the line below will summarise it such that you can solve the issues:
A unit can only cut support on itself by dislodging the supporting unit.