You don't wait. You run multiple independent incremental feature in parallel, while also running a code review, which will create the next set of tasks while you or the llm think up the feature to add after.

Context switching back and forth between a dozen different things is sort of the opposite of flow state, IMO.

It's not "flow state" but working on three features in parallel requires focus that's equally as fragile, at least if you want to follow the output of the LLMs and steer it if it makes mistakes.