One thing I find neglected in the major orchestration texts is the discussion of notation. Grammar is just as important a concern in music as it is in literature, and it is very important that we understand how notation works when stripped back to its essence. While the orchestra can be very forgiving when it comes to making sense of your notation, you will get a better performance, make your point more clearly, and save lots of valuable time and toner if you think about the impact of your notation.
The problem with the major textbooks is that they use examples from classics in the literature. Any given period or famous composer in music history, has its own performance practice that governed the interpretation of the notation. The orchestra playing Mozart knows they are playing Mozart and interprets the notation in a classical way. They have also probably played the piece many times before, so they ‘know’ how it goes without having to think. Just listen to a recording of a famous classical piece; the score may be relatively simple, but you will find crotchets played in all sorts of ways, short in one bar and long in another, because the players are aware of the appropriate performance practice for that style and piece. But when you put new music in front of an orchestra, be it at a session, a read-through in college, or a rehearsal of the LSO, they have to read the notation at face value. Understanding today’s performance practice – or more precisely, the lack of a standard practice – becomes very important, and will help you spell things out in a way that gets exactly the sound you’re looking for in the clearest and most concise way possible.