Daniel Lichtblau generously offered to lend his expert attention to the spectrum of problems linked from this Q&A:
The full list of linked questions, 26 at the moment:
It's difficult to come up with a one-size-fits-all for this. ... If you can come up with a canonical form of the question, I'll give it a try (next week; I'm traveling at the moment).
I am requesting that the community examine these many related questions and jointly pen a canonical representative covering as many cases as may be done clearly and relatively concisely.
This new canonical question should become the primary reference for this class of transformation and its answer(s) should provide methods that are easily applicable to a range of problems. It is imperative that the question lend itself to this role and encourage this kind of answer.