We use a Claude for planning and generation, sol for adversarial review. Our metrics say we are about 2x. Productive, at a cost of about $300 per dev per month. We are also shipping less bugs and better, more clearly written documentation (we use technical writing English style guides implemented by Claude)
I think a big part is the constant adversarial review by a different model with no prior context except the coding standards. Also important is context management, we do an onboarding and wrap-up for each session where we have a batch of continuity documents- Learnings, musings, and roadtrips where we let the most successful high-context sessions research and then write about something that they “ became curious about” during the session. That actually brings in a lot of insight to the team and occasionally is brilliant.
Also critical is crossing compaction barriers (standard re-onboarding protocols, writing transition documents prior to compaction, etc)
Also critical is being able to smell when a session is going off the rails. What we do there is sideline the session, wait for master to advance a bit, then have it do a “4c’s” review of the committed work, blast radius analysis, and remediation. If there’s still useful context left we put it into a project unrelated to its failure context. That salvages the valuable session context without staying in the failure trench.
It’s a lot like herding cats.