Your question to tacit, though, presumes that the
indexed metadata is what we call the
Spotlight index...
Do you mean that every Spotlight search undertaken when indexing is enabled consists of both a lookup against previously-indexed metadata and a real-time search of filenames? And that when indexing is disabled, Spotlight only performs the latter? Or is it that Spotlight still performs both searches but returns no results from the former since there's no index? (Emphasis added)
As I read, and imply from, the Apple doc, Spotlight uses the
indexed metadata for a file search and the
Spotlight index for a content search, which would explain why my disabled, theoretically index-less Spotlight behaves as described.