Agenda with an archived indicator

[Yuri Niyazov <yuri.niyazov@gmail.com>]

I am trying to build an agenda view that includes both Archived and
non-Archived items, and includes an indicator whether an item is
archived or not. Here's how I've gotten it to work so far:

In custom agenda:

(... (org-agenda-prefix-format "%(yn/org-archived-display)
%-11c%-11T%-11s") ... )

(defun yn/org-archived-display ()
  (if (get-text-property (point-at-bol) :org-archived)
      "A"
    " "))


I figured if I learned how org-agenda skips over archived org entries
while building the display, that will give some insight into what the
code inside that expression should look like, so that code is derived
from org-agenda-skip.

This has an appreciable slow-down while building the agenda, I assume
it's because it is re-parsing the item.  Is there something in the
environment of the expressions in %() that can be efficiently
interrogated for archived/not archived status?