Technique is a very specific definition pertaining to the ability to carry the task with predetermined results, given a certain amount of time, energy and resources. In music instrumentation and notation it is often up to the composer to indicate what techniques should be used for specific passages, and this is written into the score. Although there are a standard number of techniques, or articulations, used by players of certain instruments, there are nearly infinite realms of possibility for playing instruments in non-traditional configurations.
Sometimes the result of a technique is so different from what has been done before that it defies definition. One is left to use poetic words or phrases to help instrumentalists understand what to do. Even the notations at the beginning of a score, such as vivace or con vivo set the tone for the actual technique or playing style. In many ways this becomes second nature to an instrumentalist, and upon seeing the notation there will be more bounce to the bow, lifting of the horn, or a way of expressing a specific feeling that is barely a technique at all, but more of an attitude.
With groups of performers, it is common to follow an assigned or implied leader to interpret the directions or techniques. This becomes evident with string sections and how the concertmaster will establish the bowing and expression for the rest of the players. This is similar to the early classical ensembles that did not use a conductor but would follow one another to produce a cohesive performance style that would be unique to each group.
So, technique is not only an individual style that can be written into the score, but also the result of performers listening to one another and helping to optimize the resulting sound. It is created by imitating each other as well as experimenting to find out where the limits are. For each group the sound is so specific that it becomes a unique signature that is timeless.