You asked (or stated):
Is there a situation where reversing the natural word order is
ill-advised or completely wrong.
Not absolutely! And by that, mean I, no of the absolute kind. :)
I think anastrophe would best be used in technical documentation.
Window appears, click OK button do or do not. Save your settings, it
may, but if button clicked then settings may instead not be unsaved.
Click button do not, saving the settings, or exiting without saving.
Plus there is the benefit of the user not knowing whether she is to blame for not saving her settings because she doesn't understand the instructions or there is a bug in the system so this is advantageous.
Note: I couldn't resist this one because anastrophe is a great word (thanks to be introducing me to that one).
Here's my serious answer.
Why, in poetry, would there be any reason against anastrophe?
Maybe only because of overuse. Nothing should be overused. So anastrophe-on and keep on anastrophing.
The effect is quite poetic and may allow the poetry to become more rhythmic and pleasant to the ear. It may also create interesting interpretations of the meaning.