Not a slow session- but when I meet up to play I bring along written out tunes, and distribute them. I then play through any particular tune and leave it to the session members to decide if they wish to pursue learning it at home .It is often useful to carry a tune sucker with you ( cassette or MD). Slowly over the years we have amassed a large session of both standard and unusual tunes. It does help to be able to write tunes down by ear, and transpose them into friendly keys for beginners and melodeons! When I took up sax I was playing all the old easy tunes over again to learn the fingerings, and starting again as a beginner. It really helped to play the easy repertoir which I knew by heart, but was fed up with on a melodeon.