"Elsewhere one of my pet hates is when the host of a "singaround" picks out all his or her mates, and if your face/ voice isn't known to them, you don't get a look-in."
"Of course you have to know (by osmosis I think) which events are intended to be open sessions and which are actually planned to be a sort of informal concert in a bar"
My personal impressions of Sidmouth singarounds (for any intending attendees next year) are:
Kitty & Dereks – a quietish venue where people will listen to you. You'll always be made welcome and asked if you want to sing/play (but sorry K&D I never get up to make the trek to Sidmouth that early now!)
Middle Bar – "the twig rules" everyone gets a chance to sing but it's mainly for chorus songs (there used to be a NFD rule [and no, I won't translate that])
"Rosie's" (ably hosted by Dave (Acorn4) & Julia this year) – like Kitty and Derek's, you'll always be made welcome and asked if you want to sing/play.
The "Newt" (Leadfingers & Gerry) – again friendly and inclusive.
The Bedford – no "host" and you can perform if you can (a) get in through the door,(b) jump in fast enough and loud enough and (c) don't mind the noise.
The Volunteer (lunchtimes) – you'll only get a song if you are well known as one of the regulars or a festival guest BUT this event isn't really a singaround – it's an informal "showcase" event. (I don't know about the evening sessions there.)
The Ballad session (for traditional ballads, mainly Child, bothy & a few broadsides) – put your name down on the list at the door. If Sheila can't fit you in that day she'll call on you the next day if you're back and sign up.
Colin's @ the Rugby Club - put your name down on the list at the door.
Art Centre "Folk Club" – I only got to this once but they also seem to operate a "sign up" system.
All the above are singarounds that are regular events at the festival. The first five are fringe, the others are on the main programme. There are also plenty of other sessions and spontaneous singarounds which tend to be "jump in" events.
If I've missed any singarounds out, perhaps others could comment and if I've misrepresented any event, it may be a mistake but, at worst, it's just one person's personal impression – feel free to disagree and correct me. I'll leave it to others to comment on the music sessions.