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For me, I'd say if your question doesn't seem to be getting any attention, or the answers you are getting are off-track, coming to meta to ask how to make your question more clear would be okay.
If you end up with a companion question on meta for every question you ask on the main site, that might not be received very well.
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The tooltip tells you why:
So only 9 users posted, voted on, commented on, or edited something here in the last 60 days.
Only top voted, non community-wiki answers of a minimum length are eligible