That sounds like an unusually good open mic.  2 song limit is an excellent idea.  I used to go and sometimes play at those but I haven't in many years.  The main reason I stopped is that I had to bear listening to many well-meaning but awful musicians who went on song after song..if it were only 2 songs, that would be better because you could hear more folks and if somebody was particularly irritating, they'd be gone after two tunes.  Also, they dragged on pretty late, and I have to get up early in the morning and play doctor. I found that most of the "audience" were really just the other musicians in the open mic, not people who really came to hear music.  Then there might be the uncles, aunts and cousins who cheer loudly for their family member as he/she reads the lyrics and very complicated chord fingerings from a crumpled piece of paper. And if it's open mic in a bar, not a coffee house, I found the situation to be even worse.  Nobody listens, everybody just goes there to drink and talk about the football game. 

So much for open mic at least in these parts, , but man that sounds like such a good one where you are Peter,  I might even go up there to see one sometime!