Dick Claeys wrote:

>I have to draw on memory for this theory, but I believe union contract
>agreements with major symphony orchestras have something to do with the
>diminished role for overtures.  Specifically, in the late 1970s and early
>1980s, negotiations in Boston and Chicago led to an agreement that the
>normal "public performance" could be shortened from 90 minutes to 75
>minutes.   ...

Since it is still quite standard among unionized orchestras-ICSOM and
AF of M-that a "service" is 2 and one half hours, that defeats this
theory.  If concert time is 8:00 p.m., theoretically the concert can
last until 10:30 p.m.  until overtime is called.  In the case of large
scale choral, ballet or operatic works, an exception is usually made
whereas the performance can go up to 3 hours.

Gerard Gibbs