row literal problem

I'm chasing up an issue from a client who has this problem (in 9.1):

with q as
(    some query here
)
select q.* from q

yields:
                   job_scope                   | checked_col
-----------------------------------------------+------------------------------------------ Co Revenues: Co Revenues
$100to $999 Million | <input panel=data 
 
type=checkbox checked> Metropolitan Area: Austin-Round Rock          | <input panel=data 
type=checkbox checked>

which is as expected.

However,

with q as
(    same query here
)
select q from q

yields:

q
----------------------------------------------------------------------------------------------- ("Co Revenues: Co
Revenues$100 to $999 Million","<input panel=data 
 
type=checkbox checked>",) ("Metropolitan Area: Austin-Round Rock","<input panel=data 
type=checkbox checked>",)


Note the trailing comma inside the (), which certainly looks bogus to 
me. If I replace "select q" with "select row(q.*)" it disappears.

It doesn't happen in all cases, and I'm trying to work out a minimal 
reproducible example. But it sure is puzzling.

cheers

andrew