Something like that.
The long and short of it is that you have to order a certain quantity of comics to be considered a 'retailer' and it is at that point that you receive the retailer discount.
If I'm not mistaken, these calculations aren't divided according to individual product, but rather the sum of all the comics you ordered from the catalog. So it doesn't matter if you order two copies or two hundred copies of the latest Brian Michael Bendis book, so long as the total books you order are at retailer levels and qualify you for that retailer discount.
There are exceptions of course, with regards to promotional deals for specific books, though.