premise: But is the Internet so miraculous an advertising vehicle that Gross will be able to siphon off $ 400 per person from total ad spending of $ 1,000 per family -- or persuade advertisers to spend an additional $ 400 to reach each of his customers ?
hypothesis: Was the internet so rgeat at advertising that Gross would pay $ 400 per person per ad , totalling spending $ 1000 per family or persuade adversisers to shell out an extra $ 400 to reach each customer ?