I use tics to mark the ends of dimension lines ( /-99mm-/ )
When I print them, the tics are at about 1.2mm thick while the rest of the dimension line is 0.2mm (as is set on the layer).
This is only evident when I set the "Hairline width" value to 0.2 on the print dialogue (Dumb ass new fangled space ship of a printer can't work properly with PS outputs!)
OK, so I leave the "hairline width" alone and make sure that every line is 0.2 or above... it's still a bug.