Most GTD implementations treat all tasks as a single undifferentiated list, which is why most GTD implementations eventually collapse under their own weight.
The Library-as-Area Design
This template inverts the standard task management structure. Instead of a single task database with an Area field as a filter, it uses multiple Memento libraries — each library representing one discrete area of responsibility. Work Operations. Personal Finance. Home. Health. The library structure is the context partition.
The practical advantage is total separation without isolation. You work inside your Work Operations library during a work block, seeing only tasks that belong to that context, without the mental noise of home renovation tasks and financial planning items cluttering the periphery. Then you cross-reference: the built-in search runs across all libraries simultaneously, which means a project that spans areas — a house purchase touches Personal Finance, Home, and potentially Work if you're relocating — surfaces its tasks wherever they live.
That cross-library search is what makes the multi-library design function as an integrated system rather than isolated silos.
Time Cost as the Scheduling Primitive
Time Cost in minutes is the field that turns a task list into a schedulable resource allocation problem. A backlog of tasks with time costs assigned allows genuine capacity planning: if you have ninety minutes of focused work available in an afternoon, you can filter your current library by priority and time cost, build a sequence that fits the window, and execute without the constant micro-decision of "what should I work on next."
Without time cost data, every task selection is a judgment call made under cognitive load. With it, the selection becomes a simple query.
Priority H/M/L runs in parallel — filter High priority tasks with time cost under 30 minutes and you have your highest-leverage short-form task list, pulled automatically from whatever backlog has accumulated. That list is what you work when you have unexpected time and need to recover quickly.
Next Due drives the weekly review. Everything with a next due date in the next seven days surfaces as the week's commitment list. Tasks drifting without due dates are visible in the absence of that date — the filter shows what has a date and what doesn't, which makes the annual "I'll get to it when I can" items immediately obvious.
Done closes entries without deleting them. The completed task history is the archive that makes performance review and project retrospective possible.