I've always viewed the hammer test as useful for home-done application jobs, to see if your process needs to be tweaked/modified. If you finish coating some bullets and they fail the hammer test, you may want to re-look your coating process and product before loading up rounds and taking them to the range (wasting time and components).
I've never really considered hammer-testing a commercial product. I'm not going to tweak a company's coating methods, and I've already paid for (and obtained) the bullets. As others have said... "does it work?" is the real question. If they're THAT bad, the company probably wouldn't be in business (I don't tend to beta-test products... most coated bullets I've used have a been on the market a long time and have been heavily reviewed) - I'll take the risk on loading them, running them, and evaluating results.