I think you're doing the right thing. I am a fan of flaxseed. I just think people need to know that it goes rancid quickly, that it shouldn't be heated, that small amounts eaten everyday have better results than once or twice a week and that oour digestive system can't really digest the seeds whole.
Whew.
I would also suggest grooming with a brush that helps to spread his natural oils, and bathing very infrequently. What kinds of food are you feeding? That may have somethign to do with it.