Andy Cleveland asked about seisiun etiquette. I'll add the following:
1- Spend half the time playing tunes fairly widely known
2- Let beginners start every fourth tune or so, or occasionally play alone
3- Let the stars shine forth (wickedly hard tunes that no-body else
can play) about every quarter of an hour.
4- Encourage the singers to sing every few tunes, but don't pressure
them if they're not in the mood yet, or think nobody else is....
and of course:
Don't pour guinness over the erratic bodhran player
Don't leap firmly ("accidentally") onto tuneless and hapless fiddles
temporarily abandoned by their owner during a call of nature
Don't plug your ears with soda bread every time a shrill and sharp
whistle causes you pain: it's very hard to get out completely and you
really don't want mold growing in your ears.
Remove the dog that howls piteously each time a venerable singer
navigates A Bunch of Thyme.
Arrange your seating in a crowded room so that your whistle doesn't drip
un-noticed down the back of some-one's shirt, and resist shaking
vigorously near food: it makes the sandwiches soggy.
Dispose of bow hairs in a genteel location rather than surreptiously
under the meat: hairy bacon isn't popular.
Heed the subtle messages of others by stopping playing your uillean pipes
temporarily if you notice everyone has moved to a new location without
discussing it with you first.
Consider going home if you notice the host and hostess open all the
windows on a 30 degree below night, remove all the food and drink, set
out the breakfast dishes and mention they are stepping upstairs to brush
Enjoy your next seisiun with the added confidence of someone who knows
their behavior is genteel and inoffensive to all except those with
unusually keen sensibilities.
Any more suggestions?