As author of the post, I'm obviously biased into thinking it is acceptable. However, I feel I should lay out my case for the points that are raised, because I think they are indeed valid ones.
- Subjective: Where would I start? I'd start with caffeine.
I actually did not have "Where do you start" in the title. It was edited in by a SO employee. My original title ended with "Worst case scenario." :-) It was then edited by ANOTHER SO employee.
- Localized: It's unlikely that whatever solution the OP chooses will be correct for another person's problem.
I feel this is incorrect as well. There are millions of developers forced to work with untested legacy code. Even if the exact solution might not work, pieces of it will hopefully be insightful for those to come. In fact, the answer I'm "looking for" so to speak would be someone who has been down this road before (large scale legacy application that needs testing) and can give me insight on how they got the ball rolling on test.
- Unanswerable: Every answer is equally valid.
I disagree with this as well. Every answer will have equal potential to be of use, and in that case it would be worthy of an upvote, but not a check mark. While it's entirely possible an answer that addresses the issue at hand to my (as the OP) satisfaction will not appear, I would not consider the question unanswerable.
I certainly am not expecting some sqa.SE user to fly to my work, analyze our system, and come up with a solution to our testing problem. If I were, that would make it unanswerable. In its present form, I feel it is able to receive input from a number of different angles (which is good) and in that sense be useful, and is still open to get some feedback from an experienced developer or tester who has beaten this path before.
However, I should note that the SE community is open to collaboration. Your last sentence states "Does this question, the way that it written now, belong?" If you have suggestions for how to make this question less subjective and more answerable, I am most willing to hear them out as it will increase the chances of me getting actionable information I can take to my team.
And, no hard feelings whatsoever :-)