At the recent BrickFair VA there were two displays using two extremes of collaborative strategies. The brother team of Isaac and John made the completely connected Life in Nordheim
while the InnovaLUG group made the completely disconnected Ye Old Merry Battlefield
Based on this last I should revise my list above
of types of group displays:
1. Highly coordinated build of "one MOC" (e.g. the Life in Nordheim above)
2. Many separate builds with a pre-arranged standard (CCC, base8, micropolis, etc) that allows them to be connected at the event
3. Many separate builds that are combined onto one large baseplate at the event (presumably the event coordinator helped arrange for the baseplate and landscaping)
4. Many separate builds that are not ever physically connected, but have some connective thread (building style, color scheme, faction used, etc, so that when they are arranged on a table at the event they "feel connected" (e.g. Ye Old Merry Battlefield above) (or another example, at an event a few years ago different builders did different scenes from the Lord of the Rings, and they were arranged on the table chronologically so that you could see the progress of the story as you walk through the display)
5. One person (or a small team) builds a large MOC that then lots of individual builders make smaller MOCs that are then added to the larger MOC - I can't think of a good castle example of this, but a few years ago at BrickCon someone built a Battlestar Galactica hangar and then individuals built Vipers that were added to the display. In another example someone built a big Hoth base and invited people to bring AT-AT's, snowspeeders, etc for a big display. I suppose there are battle displays like this, where people bring their individual armies, siege engines, etc. Or one person could build a big harbor and invite people to bring boats.
6. Many separate builds, no connections, simply displayed together at the event
One last thought, which I buried in a comment on Brothers Brick so I figured I should repeat it here. In the Ye Old Merry Battlefield above there are little bits of landscaping scattered between the set-piece MOCs to help connect them, which was great. Another idea to create connection would be to have bits of road of consistent width and style in many of the individual creations (e.g. see this MOC
) and then arrange them in such a way that you could imagine a road winding among the MOCs. You could then have things like wagons, travelers, etc, arranged between the MOCs along the "road" to help connect them. Alternatively you could have individual MOCs contain bits of a river, and then arrange the MOCs as if they were along an imaginary continuous river.
Okay, really, one last thought. I'm not going back and looking, so I can easily be proven wrong here, but it seems that group castle displays are always summer-y. Have there been snow-covered group collaborations? Or ones using a fall foliage color scheme? Obviously the Life in Nordheim one above is wintery, but that was a connected build by two brothers. I'm talking about displays where everyone brings separate MOCs that are then combined into an overall display.