If the majority of those who work in translation are not actual translators then how do I profit by studying translation/interpretation?

First, I personally would not say that most "who work in translation are not actual translators".  If you define "actual" as "professional" (certified in some way) or "full-time" (being their sole source of income), this may be the case.  Not being certified or translation not being their source of income may often be the case.  However, it does not mean that they are not very good or not professional.

As I mentioned and probably cannot emphasize enough, the profession of a translator or interpreter (and I dare to say most language-related jobs) is like an "apprenticeship".  You cannot expect to be a good translator from the start.  Good translators are those who (1) recognize their weaknesses and (2) make the commitment to continuous learning and to expanding their knowledge.  In other words, good translators recognize their weaknesses (e.g., subjects, styles, technologies, etc.) and are willing to do over time what it takes to make those weaknesses into strengths.

A good translator, for example, is a good writer in their own language. Too many times have I worked with translators who may in fact be very fluent in their first and second languages, but have little idea how to even write in their first language.  How can a translator expect to deliver quality text when he/she doesn't even know how to punctuate a complex sentence? With this in mind, for example, it becomes clear why it is important to study writing, grammar, common/excepted uses, etc. in your native (target) language.

If you get a chance, you might read a couple discussions on ProZ.com:

• http://www.proz.com/forum/professional_development/143908-what_makes_a_good_translator.html
• http://www.proz.com/forum/translation_theory_and_practice/55956-what_makes_a_good_technical_translator.html

Enjoy and add your comments.