From a Certain Point of View

I think there's some confusion regarding when to use "a" or "the" with the expression, "point of view." What is the difference when we say "a point of view" and "the point of view"?

A and the are articles which differ in terms of specificities: when we use a, we're thinking in general terms while when we use the, we're thinking of specifics. For example, if a person says, "Bring me a bag," he or she is asking for any bag. If he/she says, "Bring me the bag," he/she wants a specific bag.

If you say, "that's the right thing to do, from a point of view," what you mean is that there could be several points of view and you are just talking about one among many. However, if you say, "the point of view," you're talking of only one point of view, there are no others. Consider the difference here:

From the point of view of the investigators, the Glorietta blast was not caused by a bomb. (The investigators only have one point of view).
That the blast was caused by a gas leak could be true from a certain point of view. (There could be other points of view or theories regarding the blast.)

If you want to talk about a person's specific point of view about a topic or issue, you say something like, "From the point of view of my boss, we should have a vacation." We never say, "From a point of view of my boss, we should have a vacation."

Don't you think we should all study proper English? That is my point of view.