You can post a share-your-knowledge style question and answer. Say, the question would look like:
How can I find out what's blocking my access to a particular PATH?
With some back story and a preface and all. And then post your script in your answer, with a good explanation on how it works and its usage.
At which point, I'll post another answer pointing to namei:
$ namei -movx /var/spool/cron/crontabs/foo
f: /var/spool/cron/crontabs/foo
Drwxr-xr-x root root /
drwxr-xr-x root root var
drwxr-xr-x root root spool
drwxr-xr-x root root cron
drwx-wx--T root crontab crontabs
foo - No such file or directory
It doesn't list what's mounted on a mountpoint, but everything else is covered, I think.