Philip Gossett in Divas and Scholars discusses so many subjects that one can free associate to ones heart's content, always a desirable thing to me. He discusses the two different ways of presenting operas: the stagione (I think this translates to seasons) system where rehearsal and performance blocks alternate throughout an opera season and the repertory system where many works can be in performing status at the same time.
The Ulmer Theater was a repertory house which rotated performances of operas, operettas, ballets and plays. It was not necessary to have a separate ballet company for the opera ballets. To present My Fair Lady staff from the opera chorus, ballet and theater company were used. It is a very efficient system from an economical perspective because something can play on the main stage every night of the year except Christmas and the long vacation.
It requires that the theater have plenty of extra rehearsal space away from the main stage. The new theater in Ulm had many spaces for administrative staff, ballet, chorus, properties, costumes and a full sized rehearsal stage tucked away in obscure corners of the not particularly large building.
In Houston, Baltimore, Chicago and other US cities the stagione system is used. Rome is stagione. A cast is hired and rehearsed, and then a series of performances is presented. When they have finished, another opera goes into rehearsal, and so forth. If the company has no rehearsal space, this is almost required.
The Metropolitan has the ultimate repertory system with up to 10 or more operas in performance in a single month. The San Francisco Opera has always been repertory, though not more than about 3 operas are in rotation at once. In the old days rehearsals took place in drafty warehouses around town. Complaints were met with the response, "If it's good enough for Montserrat Caballe, it's good enough for you." Since the construction of Davies Hall, a beautiful rehearsal stage exactly duplicating the dimensions of the main stage of the opera house exists right across the street.
If your company is presenting Tristan und Isolde, the performers are like baseball pitchers who can only be used once every three or four days. If you are in stagione, the performance block will have to have a lot of empty days. In repertory these days are simply filled with other operas. There are degrees of repertory. The New York City Opera will keep two operas in rotation.
Gossett is worrying about the subject of performing editions. There are often many potential versions--all authentic, legitimate versions--one might choose when performing an opera, especially an Italian opera from the nineteenth century. His attitude is to encourage this, and he believes that the stagione system works best for a situation where a non-standard version is to be presented.
I am finding this all fascinating. It makes me think I should inquire about the version that will be used to present The Siege of Corinth in English next month in Baltimore.
My own feeling is that the amount of available rehearsal time is the crucial issue. If a work is presented over the course of a long season, with the changing casts this often involves, then the use of non-standard versions becomes less and less likely. Large blocks of rehearsal time for secondary casts is unlikely.
In the German theater system most singers are contracted to a single house, but there exists also a short list of singers who are available at a moment's notice to come in and perform an opera to fill in for a sick singer. These people are not understudies, but are independent contractors. This is a fascinating experience. Usually the cast assembles an hour earlier than the normal time, meets the new substitute and walks quickly through the blocking. Tempos are briefly discussed. This is the ideal situation; there may be even less time than this. Then the singers don their costumes and the performance begins. However, I do recall once looking down into the pit after my entrance and seeing a complete stranger conducting. "Und wer bist denn du?"
Obviously, this system does not allow for the concept of alternate versions. To slip someone onto the stage on less than a day's notice, they need to already be familiar with the score.
When Rossini and Verdi were composing, it was assumed that there were many possibilities. Many operas were rewritten to take advantage of the talents of mezzo-sopranos Maria Malibran and her sister Pauline Viardot, for instance. The composer saw his own success and the success of the singers as identical. As a result, many alternate versions of verious levels of quality exist for these operas.
The main barrier to Gossett's vision seems to be money. Operas are performed in the original language to allow performers rehearsed elsewhere to assume the roles, because rehearsals are expensive. To perform alternate versions singers will need to unlearn and relearn roles already in their repertoire. Using alternate performing editions is an expensive but interesting idea.