I think the coasting idea is great. Also, can you raise the training wheels so they are a couple of inches above the ground? That will let your ds get used to the trick of balancing without having to fear falling over.
I think I was 7 when I learned to ride without training wheels. It was not a pleasant experience for me, but I think it might have been downtrigh traumatic for my parents...
Looking back, I wonder -- Why? What was the high stake situation here?
Anyway, it took -- in addition to the types of things mentioned above -- LOTS of bribery (for me, it was in the form of lots of dinosaur and other animal models). So, you might want to sit down with DS and figure out some sort of incentive system.
The good news is, once you get over that hump, then ta-da, the kid can ride the bike and the issue is basically over.
