There's a devising project I do with some old friends who now have proper jobs. Without wanting to damage the secrecy of the room, I want to clarify my thoughts on some things. Specifically, wasting time.
For me, it's a great way to practice devising technique and work with people who bring ideas that I'd never find in an artist-only room. It's also very pleasant socially.
However, our usual three-hour session is one hour talking, then an hour and a bit of actual devising, until pizza shows up and we get distracted.
Indeed, in many of my rehearsal rooms I start the actual work a bit later than the scheduled time because we're talking. I know some people view this as a tremendous waste of time, but I feel like it has some useful benefits. Arranged in order of abstraction/pretentiousness:
First, it helps bond the group. Humans bond by sharing social experiences, and chatting is an easy one to include. At its most basic level, 'group bonding' is the reason for time-wasting in rehearsal rooms.
Second, it gives me an idea of where people are at. The conversation will normally reveal explicitly or implicitly who is ill, or unusually happy or sad, or preoccupied with something. That means I can adapt the rehearsal around that, giving people space if they need it, focusing exercises towards people who are particularly keen, and generally adapting behaviour to suit my collaborators.
It also (in a more flexible process) gives a sense of what ideas people are currently thinking about, and might bring into the room. If someone's talking a lot about Brexit, it's fairly likely their creative thoughts that day will tend towards the political.
Third, it helps set the rehearsal room's tone. Most of my recent projects have had a comic element; letting people chat and mess around creates a consequence-free(ish) space to be creative in a form they're comfortable with (i.e. everyday conversation). That then feeds into the actual work, where people (I hope) feel as respected in their creativity as they do in their conversation.
Fourth, it helps relax the room's hierarchies. A well-managed pre-rehearsal chat can help level the field between the traditional top of the pyramid (director/conductor/anyone famous) and the bottom (the observer/the person in their first role/the band), giving equal space to everyone, and letting people see each other as humans.
'Well-managed' is important in that sentence. Without it, pre-rehearsal chat is a few bigshots talking over everyone else and reinforcing their power/privilege. With it, you can establish an expectation that people should be mindful of each other, not interrupt, and other such useful codes.
Fifth, 'inefficient' is a rubbish term for art. To unleash my inner academic Marxian, most artistic processes are based on a premodern model of craftsman-creation. That is to say, they privilege individuality and personal technique in the act of production, rather than industrial processes which price group action, efficiency, and conformity (as on a production line). When people start talking about efficiency, or measurable outcomes, it's important to remember that most art doesn't fit these criteria. When it does (such as in some formulaic Hollywood films) we tend to get uncomfortable about calling it art.
So pre-rehearsal chat is inefficient within a modern model (especially a neoliberal one) but very important in a model that still prizes individuality. Social rituals can uphold the individual as an individual, as well as a part of a larger whole.
And it's nice to have a natter.