Doing any course is an advantage, you always learn something, if not from the course, then from other students.
If you are the solitary type, then it does good to mix with others now and again.
Disease ID is probably the most important.
As for having the qualification. There are lots of people who are highly qualified in certain fields. it just means they can pass exams.
"Qualifications will help you get a job, but they won't help you keep it." That's where BullSh*t come in.