Visualize a relatively simple double-sided plated-thru-hole PWB made from
.062 thick FR-4.  It could be a few square inches or a hundred.  There are
many areas that do not have traces in them.  Further, visualize a few dots of
metal that eluded the etching process in these non-functional, otherwise bare
areas.  They might vary from a dot of .050" diameter to a line .050" x 1"
long in a sea of open and otherwise etched clean FR-4.  The "unwanted" metal
is firmly affixed to the board and easily passes the most rigorous tape test.
 None of these pieces of metal reduces spacing between conductors in any way.
 The PWB is otherwise totally functional with these items being cosmetic - -
- however, in the board's final use it is hidden deep in the user's
equipment.

Are these acceptable to IPC specifications?  Reference to specific specs and
paragraphs would be appreciated.

Do the metal areas need to be removed?  If so, why and how?  If they are
scraped off and the FR-4 surface is scratched, does it need any post
treatment?