>Also, why are both teams working in isolation for a month? If both teams check in code, the checkins themselves can provide an indication that other people are working in the same area. Incidentally, it's this effect that makes me strongly dislike feature branches. It's better to develop unstable code behind a feature flag, where the code is visible even if not active, than in a feature branch, where nobody can see it.
I chose my example carefully, the 'new' launcher being developed officially was part of a new, unannounced product, and therefore likely secret prior to release. On the other hand, the new version developed by the two people was a top to bottom revamp, which might mean an entirely new application, or something that can't easily be done behind a feature branch.
>Personally, I'd rather see two teams work toward our improved hypothetical launcher than to see zero teams do that work because process imposed too high an "activation energy" on the launcher experiment.
And again, I chose my example carefully: one team would always have created this new launcher, it was creating something as part of a much larger initiative.
>I'm not suggesting that communication is bad. I'm objecting strenuously (perhaps stridently) to the design document as a step in a rigid process and a requirement imposed from above.
Indeed, but if nothing else, a design document is a formalized process for this type of communication. To be clear, my understanding is that Google also has best practices in place for objections and blockages to things proposed through design documents.
The result is that when you are planning to create a feature that is large enough that it is, shall we say, statistically likely to break things or cause someone else serious aggravation, there is, if you are following policy, a formalized process for informing the people who your change might impact, a way for them to provide feedback, and a formalized way to resolve conflicting opinions when each engineer thinks that their workflow or feature is the most important.
This goes back to the other example I gave, which was a real one, where my design documented project could have, if implemented, created a situation where, until rectified, breaking changes would have gone undected by automated tests, and instead shown themselves in the tests for unrelated changes, which would have been an annoying bug to track down, and would have caused some other team a lot of stress and time. They would never have been notified until final review, and conceivably could have been months of wasted effort on my part.