SGPsychStud: Jack of all trades or Master of one?

Coming into the season of work appraisal, this is a question that I have been asking my fellow colleagues:

"Do you wish to be a Jack of all trades or Master of one?"

Often in work, we are asked to do a lot of things, however most of them may be pertaining to our line of work, e.g. writing clinical reports, preparing and researching information for upcoming meetings, etc.  Doing these things are fine as they belong in your area of expertise, and were what you expected to do when you interviewed for that job in the first place.  These things are also the job requirements that your employers expect you to be equipped with in the first place.

But sometimes we are also asked to do other "non-expertise" things in the areas of event management, marketing, HR, etc.  This is unavoidable and you cannot often say "No" to your own boss or employer.  In my opinion, it is okay if I have to do it once in a while, but it is not conducive to work if that is all I am expected to do instead of the above "expertise"-related work.  It is sometimes made worse, knowing that your work appraisal is going to be based on these "non-expertise" work.  Imagine getting evaluated for your skills in managing a company event when you are employed as a psychologist?  

We are in a society that wishes to improve all the time (due to our ability to find faults in everything).  Hence there is the thought that we need to be well-rounded in different skills; however, are these extra skills the skills we personally want to have?  Will these extra skills help us in our ability to be a better psychologist or employee in our line of work?

This question is also faced by some psychologists.  They may choose to say that they practice eclectic psychotherapy, which is a combination of different therapeutic techniques.  But it is also said that eclectic psychotherapy is practiced by those who are not knowledgeable and skillful in one single therapeutic method, hence they decided to "mix and match" different methods (i.e. jack of all trades).  So would you choose to say that you are very knowledgeable and skillful in one (or a few) types of psychotherapy or just use whichever method (which you learned briefly) that seemed suitable during the session?  But how are you going to attain and practice these "expertise"-related knowledge and skills if you were often asked to do "non-expertise" tasks at work?

This is written from the author's personal perspective working in the public service.  Your current work situation might not be the same as the case above.