This is a generous offering of expertise, but supposing you were to help him out and he were to take on implementation costs, wouldn't "Here's what I'd do to get you to a billion impressions a month of customer demand for your product" be a higher-priority task than saving a few hundred bucks?
The most common failure mode in scaling for startups is to have no scaling problem at all.
Costs that are that out of whack with expectations would usually indicate some very low hanging fruit. If you can save $800/month by adding a couple of database indexes and tweaking your config file, then yeah, it's worth it.
That said, from what Maciej has written in the past, he sounds competent in these things (i.e. has his databases set up for remote replication and failover), so it would seem that the culprit is more likely over-engineering than under.
I think his questions aren't meant to signify an offer expertise but rather say this base level of knowledge and data should be available whether you're on a shared hosting account or run your own Tier IV center. He's not suggesting a rearchitecture, he's just suggesting know the environment. Decisions are wishy-washy without evidence.
The most common failure mode in scaling for startups is to have no scaling problem at all.