Anglo wrote

"I remember Peggy Seeger (with Ewan MacColl) stopping a song at the first chorus because most of the crowd hadn't got a particular note right. She taught the interval required and then they continued."

What an unhappy memory that brings back! I remember Peggy (with Ewan) teaching a chorus to a packed club in Brighton in the early '70s -

~~~~~~~~~~~~~~~~~~~~~~

Five times five are twenty-five
Six times five are thirty.....

Now all sing that.......

No, no, no. Some of you are singing thirty..... (Peggy demonstrates two syllables on the same note)

It should be be thirty.....(Peggy demonstrates the second syllable dropping a fifth)

Lets all try that again.......

And once more just to be sure......

Now the rest of the chorus. I'll teach in in short sections.....

~~~~~~~~~~~~~~~~~~~~~~~

You'll have to believe me that this went on for about ten minutes by the end of which about a quarter of the audience had walked out.