It is a foolish thing to draw grand generalizations about theater audiences. But here goes.
I cannot speak for large, commercial houses. I haven't had enough experience with them. My time spent in front of (or behind the scenes for) small, alternative theaters is vast and aged. And I make the following observations about weekend audiences.
(As a caveat, this is based on productions which have been well-advertised or have good word-of-mouth.)
Friday night: Loud and open for a good time. The assumption being, anyone who came home from work, had dinner, and made it back out for curtain (especially a 7.30 curtain) are loopy, week-addled and out for a good time.
Saturday night: Bigger turnout than Friday, and suspiciously quiet. They've had all day to relax, and show up at the theater relaxed. And they haved chosen this show for their big night out for the weekend, and it better be good. We call it the "Impress Me" audience.
Sunday matinee: House of ten, maybe eleven. No one sees theater on Sunday - except for senior citizens, and other actors who had shows that weekend, but no matinee. Grab bag. The actors in the audience could make it louder than Friday.
It is a foolish thing to draw grand generalizations about theater audiences. But my Friday and Saturday night fell neatly into those two categories.
I'm not saying last night didn't go well, it went extremely well. But the energy of Friday threw me, and when I was getting less response it threw some delivery - and sharpened some of the scenes.
When you are alone onstage, it is challenging to repeat ... since no one is feeding you lines to react to, you can fall into moments when you think, "Didn't I already say that?" Yes. You did. Last night, say it again.
One more performance. I need to keep going over the script, luckily I have all of Jeff's show to look it over. I remember being in the dressing room in Minneapolis, looking over the script for I Hate This until places. I think I am in a good place.