From: Robert Sanderson
> <> a bf:Title ;
>   bf:value "Lord of the Rings" ;
>   bf:identifier [
>     a bf:Identifier ;
>     bf:assigner "Rob" ;
>     bf:identifierValue ""  ] .
> Really? Really?! :)

Rob - I'm trying to work my way through all this, and right now trying to figure out your  example and if it is legitimate. 

Compare with Thomas's example:  (At least I think it was his, it's hard to tell who said what.)

<> a bf:person;
   bf:identifier [
    bf:schema "VIAF";
    bf:identifierValue "195531823";
     bf:identifierValueURI <>

In his example, the identifier is for a person (bf:Person, which is an Authority, which is a core class). There is an identifier scheme (viaf), a value within that scheme, and the identifierValueURI simply turns that value into a URI. (And if you prefer to put the URI in quotes and treat is as a literal, fine.)

But Rob in your example the identifier is for a Title. (I don't think we've thought much about providing identifiers for titles.)  It would help if you provided a scheme (whatever it is) and an identifier within that scheme, to help make sense of the example.   (And it's quite possible that I'm missing the point. Wouldn't be the first time.)