If all he's doing is parsing search results, then nobody would be seeing his advertisements. You conveniently left out the part where he uses a bunch of different Twitter accounts designed to appear to be different people.
I agree, but the general point is that specific marketing tricks that work well should be hoarded, not shared, because sharing them destroys their value.
Because it'll lower your competitive advantage? If your main competitive advantage is knowing about some cheap Twitter trick--sorry, I mean "Growth Hack"--then you need to rethink your game plan.