I do not believe that locktitle is inherited in DITA 1.0:
http://docs.oasis-open.org/dita/v1.0/archspec/dita_spec_23_mapinher.html
This also pertains to the other email where you discussed the pernicious
effects of inheritance in one context.
> -----Original Message-----
> From: Robert D Anderson [mailto:]
> Sent: Thursday, February 23, 2006 12:09 PM
> To: Paul Prescod
> Cc:
> Subject: Re: [dita] Navtitle and locktitle
>
> Hi Paul -- yes, that has also been my understanding. For our
> users in IBM, we've created an editor macro that goes through
> to refresh all of the navtitles in a map, though we do not do
> it automatically. As with your description, the macro does
> not update navtitles for anything that sets or inherits
> locktitle="yes".
>
> Robert D Anderson
> IBM Authoring Tools Development
> Chief Architect, DITA Open Toolkit
