Hi Omar!
This article was superb! I encounter this very issue on a regular basis, not only in my professional life, but in my personal life as well. I am a Washington State Certified Social Services and Medical Interpreter, and a Staff Interpreter at Camino Del Rey Church (Bilingual Spanish/English). The Pastor is from Argentina, but many people in the congregation are from Mexico, El Salvador, Nicaragua, and other parts of the Spanish speaking world. I have also interpreted for guest speakers of English from Australia into "Spanish". It can be very frustrating when you have a mixed target audience and you don't have the option of using several different words to ensure that each person from the different Spanish speaking countries understands your general message. It is much easier when you are dealing with one individual or a homogenous group...I guess that is what makes an interpreter's life more exciting and challenging. We can never afford to stop learning on all levels!