My argument for this:
1. Using a subquery does not preclude us from using join in the main query (probably inefficient - need to explain plan to get numbers)
2. There is only a couple of lines of hand coded sql.
    a.  The first line is essentially a no-op for type coercion.
     b. The second one is a straightforward join in order not to get duplicate joins.

What do you guys think?