I've never thought of this as a problem with the neck joint, but a lot of factory seconds I find have thin lines of excess glue along the heel. Don't they finish the guitar with protective coating AFTER gluing, and if so, shouldn't this cover any excess? Could there be a problem with such guitars after all?

it's possible that the cosmetic issue of the glue not being cleaned off is WHY the guitars are seconds. i can't see why there should be a problem from this.
The neck is usually, Not always, glued on after both the neck and guitar are finished. The glue should have been cleaned off before it set but obviously wasn't Won't affect the guitar at all. It's just cosmetic.

It would be a second because musicians tend to be such perfectionists that they would go apoplectic with this and get on a forum and bash the brand no end.
^ What they said. Basically, someone was just sloppy.
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