Yes. A could support B to hold while B supports C to hold.

But, that will not protect B's support of C from being cut. It will only protect B from being dislodged.

Oh, yes that way two. Two units can support each other to hold. Happens all the time.

Err, that way too, not two.

As long as the army being supported isn't moving, it can be support hold-ed... so you can support hold a unit that is supporting a hold, supporting a move, convoying, or just holding.

great thanks i just didn't want a mix up

Hold up-- that doesn't always work. When you introduce coasts, things get screwed up.

Remember that a unit can support the hold of another if it COULD move to that unit's territory. (Obviously no actual movement is going on)

It's best to demonstrate with an example... Army Norway can support the hold of Fleet St. Petersburg (north coast), and the fleet can also support the army since you can move from StP/nc to Nor. But what if the fleet were on StP/sc? Well, the army in Norway can move to StP, so it can support the fleet even though it might seem to be on the "wrong" coast. However, since you can't move from StP/sc to Norway, the fleet CANNOT support the army in this case.

The same holds for a fleet on Norway, incidentally-- a fleet in Norway could support a fleet on StP/sc even though the coast it can move to is StP/nc.

You can find similar examples with Gascony supporting F Spain (south coast) or Marseilles/Gulf of Lyons supporting F Spain (north coast). In either case, the Spain fleet can't move to the other unit's place, and so the support is one way. And by this point you should figure out how it will apply to Bulgaria.

So to answer the original question-- most of the time you CAN support symmetrically, but when separate-coast territories are involved things get hairy.

So would it be possible to generate an three-point support - e.g.:
A Ber S A Muc holding
A Muc S F Kie holding
F Kie S A Ber holding

???

Yes, but remember that any one of them can be broken