...
If anyone ends up doing some dwarfy science on this I'd love to hear about the results.
... I can't confirm, but I have personally seen strong evidence that the need to uphold tradition is associated with wether your fort dwarves will start a dance or not (they may recite poetry also, or just play a song). ...
Recently, the dfhack structures were updated to include some very nice details surrounding performance abilities (poetry, music, dancing, instruments) so I was able to adapt some of my scripts to do some testing.
My test methodology is pretty straightforward. Immediately after embarking, I create a 31x31 tavern on the surface, and typically, in a few days, if the world is ideal for that sort of thing, visitors show up.
I've worked out that without historical figures or sufficient civs, you get almost no visitors. Not surprisingly, in a world with a dead dwarven civ and no other civs of any kind, you get no visitors. Makes sense.
With many human, dwarf, and elf civs, you get many visitors. In some worlds, if goblins have become citizens of other civs, or their sites have been taken over by non-goblin civs, you'll even get goblin visitors. Similarly, if animal men become citizens of civs, they too will visit.
So, visitors are arriving, but now.. we want them to dance. Of course.
There's a few different mechanics at play here. There's needs, personality traits, values, skills, and preferences.
From what I can tell, personality traits and preferences don't have a significant bearing on whether or not dances happen.
It may be that in extreme cases, they might, but I tested with reasonable, average, or ideal personality traits and preferences, and those didn't seem to make any difference.
Once the various dances were setup as Legendary in skill, what DID seem to make the most drastic difference were the needs and values.
In particular..
unit.status.current_soul.personality.values
of
[df.value_type.MERRIMENT]=41
along with, optionally
[df.value_type.ARTWORK]=41
[df.value_type.COOPERATION]=41
and
unit.status.current_soul.personality.needs
of
[df.need_type.MakeMerry]=2
[df.need_type.AdmireArt]=2
and optionally
[df.need_type.UpholdTradition]=2
However, some context..
My goal in testing was to see if it's possible make all the dwarves perform social dances only, and often. Turns out, you can.
I gave all the dwarves in the fort all the social/group dances in the world, regardless of origin civ, and then made them Legendary(20) skill at those social/group dances.
I also gave them lower skill in all their civ-specific poems and music, and legendary skill in all their civ-specific instruments.
Turns out, instrument skill has no apparent bearing on whether or not a dance will be performed. If they don't have that instrument or instrument skill, they will just simulate it, if it's required.
The UpholdTradition need is apparently only fulfilled if a dwarf participates in a dance. As some social/group dances are a group of 2, and observing those is part of some dances, this is a somewhat risky need to have in place. Personally, I don't use it, but I wanted to test Jundavr's premise. It often appears true, for participation/performing, but I've seen the need unmet immedately after performing, so it's not 100%.
If a dwarf observes a dance only, the UpholdTradition need will not be met, from what I saw.
It may also be true (I only saw this once) that having UpholdTradition as well as MakeMerry and AdmireArt does create a biased selection of
more frequent Dancing after Socializing.
All of the above was also tested with an ever present ..personality.needs of:
[df.need_type.PrayOrMeditate]=0, -- this actually presents itself as a need to pray, even with a value of 0
[df.need_type.DrinkAlcohol]=1 -- as a control, given this is a common feature of all dwarves.
In short, if they value MERRIMENT and have a MakeMerry need, and if they have high skill in dancing, they will dance. Often, but not exclusively.
Under my test conditions, where all other needs and values were removed or left at the default, they participate in exactly five tasks/jobs while in a tavern:
Socialize (this is the default/expected/normal)
Listen to Story
Listen to Poetry
Listen to Music
Dance (watch/participate)
Under these test conditions, what I've observed is they start with Socialize, then branch to one activity of: Story, Poetry, Music, Dance, then back to Socialize, then one of the performance abilities, and that repeats forever, until they need to eat, drink or sleep.
Of course, if there is another meeting area, or a temple, or you assign them a job in a workshop, those get done in between. But when they're just living life, and there's just one tavern, that's what happens.
If they watch a dance, listen to a poem, listen to a story, or listen to music, this counts as AdmireArt and MakeMerry, and those needs are met. With only those needs, it's quite easy to have un-stressed dwarves, all other things being equal.
Some exclusive needs (BeWithFriends, TakeItEasy, StayOccupied) result in many No Job tasks, and as a result, no Socializing/Dancing.
BeCreative, as a need, seems difficult to meet/fulfill. It may fit into the UpholdTradition category, where you can't just observe, but have to participate. This makes it a harder need to meet.
I haven't tested:
all the personality.needs, exclusively
all the personality.values, exclusively
extremes (both positive and negative) for needs, values, and personality traits.