I agree very much with you that interruptions are death of productivity. Your suggestions for weekly rotations are great.
However, I argue that if the engineers are interrupted by QA issues, they will be motivated to find ways to not have those QA issues. In absence of that, we end up with the familiar “feature complete, let QA find bugs” situation.
> However, I argue that if the engineers are interrupted by QA issues, they will be motivated to find ways to not have those QA issues.
There are institutional limitations that engineers cannot overcome, no matter how zealous or motivated. Moreover, companies also ought to remember that engineers can "find ways to not have those QA issues" by seeking employment elsewhere!
However, I argue that if the engineers are interrupted by QA issues, they will be motivated to find ways to not have those QA issues. In absence of that, we end up with the familiar “feature complete, let QA find bugs” situation.