I agree. In the story that my teacher was critiquing at the time, there wasn't really any justification for suddenly introducing a new point of view in the penultimate section. However, the story I just finished a draft of revolves around the contrast between two different main characters' points of view that, as such, must alternate throughout, and I think it works.
One of my favorite short stories, "Division By Zero", published in one of the Full Spectrum anthologies, used the proving of mathematical theorums as a framing device. It swapped between the two characters' POVs each section, labelling each text section "1a", "1b", "2a", "2b", and so on, just as you would label each step in manipulating the mathematical expressions in each column to eventually equal each other. This obviously sprang from the central conflict of the plot, in which mathematics is key, but also developed a theme in which you could think of these two characters as the two progressions of mathematical expressions that hope to come out "equal" by the end.
Wow, I hope that made sense. Anyway, it can work, even in very short stories, but the shorter the tale, the more careful I think one has to be that the multiplication of points of view is actually necessary and useful. (Sounds like we need a paraphrase on Occam's Razor here, something like "points of view should not be multiplied unnecessarily.")