Unused ERR_TEMPLATE_EVENT_* language strings in en/common.php

in file en/common.php:

'ERR_TEMPLATE_EVENT_LOCATION' => 'The specified template event location <em>[%s]</em> is improperly formatted.',

I'm not sure what is improperly formatted. Is it location of event or event itself.

I sent it first to the forum, but was told by Bantu to send it here.