You can use incremental percent complete values for simple checklist tracking. Here are my recommendations on when and how you might do this without falling into the "precision is not accuracy" trap of project management.
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That statement is precise but not necessarily accurate. I've previously discussed some of the problems of tracking progress by percent complete. Recording percentage complete per task is easy enough in Project; the Tracking toolbar includes handy incremental completion buttons, and if 25% increments are too vague for your needs, you can record any percentage value you wish in the Update Tasks dialog box.
No, the issue with tracking progress this way is that it may suggest to the project manager and project stakeholders a higher degree of precision than is warranted. Because Project always converts percent complete values to timephased actuals, you get seemingly precise actuals whether you want them or not. Remember, precision is not accuracy.
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Here's what I'm referring to. Let's say that I want to record that task 3 is 50% complete. I do so via the handy 50% button on the Tracking toolbar. Easy enough.
Now when I switch to a more complex view, in this case the Task Usage view, I see that Project has recorded that 50% complete as timephased actuals on the task.
Although I didn't directly enter these actual hours per day for the assignments on the task, there they are. There's really no avoiding this detail though. Project is, as expected, just doing the math to keep the scheduling formula accurate: Duration times Assignment Units equals Work.