[O] Agenda filtering (take 2)

[Richard Lawrence]

Hi everyone,

About a year ago, I wrote: 
> > Is there a simple way for me to say to the agenda, "Show me all 
> > (and only) the NEXT tasks that are part of a project whose 
> > deadline is before (say) 2016-11-01"?  It seems like this 
> > should be possible with the built-in agenda but I can't quite 
> > figure it out.  The tricky thing is filtering by the deadline 
> > of the parent project, which might be several levels up. 

I'm still stuck on this, so I'd like to ask this question again. 
Bastien responded: 

> I would add a category to each project, then use something along 
> this: 
>
> ("N" "My important tasks" tags-todo 
>  "CATEGORY={cat1\\|cat2}+TODO={NEXT}+DEADLINE<=\"<+3d>\"") 

But that doesn't seem to work for me.  The problem is that the 
tasks I want to list in the tags-todo search don't themselves have 
deadlines; only their parent projects do.

I have a file with projects that look like this:

** TODO Foo University 
  DEADLINE: <2017-11-01>
*** NEXT Determine application requirements for Foo U.
*** TODO Submit application

I'd like to see a list of just NEXT tasks in this file, sorted by 
the deadline of their parent projects.

I thought that property inheritance would be the way to do this. 
So I tried: 

       ("jn" "Job application NEXT tasks" tags-todo 
        "+jobmarket+application+TODO={NEXT}" 
        ((org-use-property-inheritance t)) 
         (org-agenda-sorting-strategy '(deadline-up)))) 

as well as

       ("jn" "Job application NEXT tasks" tags-todo 
        "+jobmarket+application+TODO={NEXT}" 
        ((org-use-property-inheritance '("DEADLINE")) 
         (org-agenda-sorting-strategy '(deadline-up)))) 

in org-agenda-custom-commands.  But neither seems to work.  Can 
anyone provide any insights here?  Is it possible for sub-tasks 
within a project to inherit their deadline? 

Many thanks as always!

Best,
Richard