I think it says, "If an argument matches the first entry in @EXPORT_OK, then do the heavy (general) form. Even if said argument (and all arguments) contain no non-alpha characters (including sigels).

Likewise for the fail array, but I don't know what that's for yet.

Module buggy? Well, calling export_to_level was reportedly buggy a year ago, so who knows? If it mistakenly runs the general form, it will not malfunction, so a mistake in this logic could indeed go unnoticed.

I'm wondering if it's to support a feature that got dropped. Maybe the first entry in @EXPORT_OK was to mean something special?