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The auto-suggest feature is quite useful when asking questions but since including tags in the title is discouraged (unless they are intrinsic to the question), the auto suggest doesn't always have sufficient context to provide a good suggestion.
If the question is long, by the time you've entered tags, the suggestions are no longer visible. You (at least, I) don't always notice a good existing question which solves your problem. Quite often I'll be asking a question on (say) Python and see responses related to .Net. I habitually use multiple languages as do many of us (I have no idea if it uses my preferred tags/points too?)
I'd suggest that by moving the tags below the title, the auto suggest feature could infer more context and provide more relevant suggestions.