Spreadsheets strain the moment a task has more than one tag. But “schedule a dentist appointment” needs a phone and it needs to happen during business hours. That’s two contexts, and a spreadsheet column wants to hold one. I built a multi-tag version once, with helper columns and nested filters, and it broke all the time. So I told you to keep it to one tag per task, and to know that was a compromise.

Here’s the compromise removed. In the app, a task carries as many tags as it actually has, and, this is the part that matters, when you filter to a context, the results are still ranked by importance. That combination is the whole point, and it’s the one thing a spreadsheet genuinely couldn’t do gracefully. Picture the coffee-shop moment from Part 3 again: you’ve got your laptop and an hour. You filter to “computer,” and what you get isn’t just the tasks you can do here, it’s those tasks in order of importance, the most important computer-task sitting right at the top. “Only what I can do where I am, and among those, what matters most.”