For emerging product-market fit companies, your power users are your lifeblood. Cultivation super-users early is the make or break for seed companies. These super users are testers, referrals, product-definers, everything. 50M+ user problems are just so limited.
In any case, great talk, but definitely targets growth marketers more than start-up folks. Especially liked the idea of tying 'magic numbers' to logical reasoning, not done enough in the growth world.
Edit: Much better in the tactical section going through marketing tactics.