Resolution: Won't Fix
As pointed out in ...
Bug 7502373 : PAGEDEF FILES NOT CREATED UNDER PAGEDEFS PATH FOR JSPX CREATED IN SUB-DIRECTORY
... and some OTN forum threads , Page Definition files can end up "all over the place"
(also illustrated by http://www.consideringred.com/files/oracle/img/2011/PageDefLocations.png ).
But bug 7502373 currently has "Status 32 - Not a Bug. To Filer", so it does not look like this behaviour will be improved in the context of this bug 7502373.
- (q1) Why does bug 7502373 have "Status 32 - Not a Bug. To Filer"?
- (q2) Do any other bugs (or enhancement requests) exist that try to improve (the consistency of) the location where Page Definition files are created?
A related suggestion was done in JIRA issue
-  https://forums.oracle.com/forums/thread.jspa?threadID=723955