The data  in your column  would live in a database. If you can find where
that lives, you can use SPD to create  anything you want to see based on
that data. You may also want to look into workflows. That is kind of
what it sounds like you are doing.

Workflows may work in one strategy, and that is to populate the
column within the sub-site  as the main one recieves new entries.
However, that is sloppy, as it still is being duplicated rather than
based on one source of accuracy. Any idea how i would utilize SPD to
zone in on that column  from the subsite?

It seems like I found an easier way. I am sure others will have
something to add.

There is a web part called "I need to". You can set that up to point to
an existing project. It will list  all tasks based on the filters you
set. Unfortunately, there isn't a filter to only show tasks assigned to
you. However, you can then add another web part called Current User
Filter. This filter allows you to only see the things for the current
user. You can also set one up for viewing other specific users. You
will see once you add that filter, it will ask you what to apply the
filter to. Point it to the "I need to" web part and you should only see
your stuff. You will then see the filter option show up on the "I need
to" web part.

I hope this simplifies things a little for you.