How does VARA affect the long-term relationship between a public art agency and an artist?

One of the results of the Visual Artist Rights Act has been the establishment of a more formal and prolonged relationship between the artist and the commissioning agency.  This relationship is typically further enumerated in the contract for the commission.  
When there is an issue with an artwork, such as damage or changes to its site or context, then the owner of that artwork should communicate directly with the artist.  This benefits the owner and the artist, both of whom have a vested interest in the wellbeing of the artwork.  As a matter of best practices, if an artwork needs to be removed, then the artist should be given the first right to regain ownership, remove the artwork, or disclaim authorship, even if VARA rights have previously been waived.