Cracks in Chimney Bricks: Repair or Replace?

One of my chimneys was recently repointed. The contractor was supposed to replace any bricks that needed to be replaced down to three courses from the top. When I recently went up on the roof, I discovered that bricks in the second and third courses were not replaced and still have cracks. Photos (with close-up) are below. Contractor is balking at tearing down the courses (and is not a bad guy, did other work on the house at a decent price)--so I'm wondering whether those bricks actually need to be replaced or whether they can just be filled in. Or maybe there's some other solution. Thank you very much for any input you can give. (Not sure if relevant but, the chimney is on an exterior wall. I live in Maryland, so it can get kind of cold and snowy at times.) Attachment 50037 (http://www.doityourself.com/forum/attachments/bricks-masonry-cinder-block-paving-walking-stones-asphalt-concrete/50037-cracks-chimney-bricks-repair-replace-pic-1-1.jpg)