I don't actually apply more wax to my pipes until I can no longer bring up a luster by hand with an old Tshirt. I just buff them out with some elbow grease and a good bit of pressure with just the old shirt. Then, if I can't get any luster at all, I will consider adding more wax. About 90% of the time, just buffing by hand works best.
The problem for me, when I add more wax, is that after smoking it and warming up the bowl and touching it, the new wax just dulls right away anyway, requiring more hand buffing. But, if I just buff by hand to begin with, it is less likely to dull as quickly.
I think this is due to new wax being added to such a thickness that warming it immediately dulls it. But, just buffing the existing microscopic layer bring up more of a luster that lasts longer.
This is just my experience, but I thought it might help.