Policies implement the intent of the salmon run. By placing unrestrictive policies to the left, I can checkpoint my work frequently. By placing restrictive policies on the right, I can maintain the stability of releases. And by incrementing the restrictiveness of these policies in small steps, I reduce the backlog of code that is “trapped” towards the left. Compare this to a centralized VCS, in which (since there’s no local repository), developers may keep changes out of VCS for hours or days (since the alternative is making a central branch, which is expensive to create and expensive to tear down). Or compare to a DVCS system without an index, where the overhead of either making and tearing down branches, or of pruning temporary commits, can discourage a developer from making a checkpoint every minute or 2. (At least they discourage me, even though these operations are far less expensive than with centralized VCS.)

i like the notion of having chained stores with increasingly higher bars between them. pretty obvious between head and release branch, less so between working dir and head