I found when I tried doing this "calibration" phase, that it's not just about sheer time spent on a task.
A task that took three 1-hour sessions is often not doable in one 3-hour session, because you lose creative productivity after a bit of time. That was my first mistake when trying to estimate how long things would take.
Instead, now I calibrate based on time as well as sessions, so I know preparing a new 80-minute lecture (for a class) takes two 5-hour sessions: the first 5-hour session to outline the class and activities, gather the major sources and bullet points I want to make; then the second 5-hour session to put together the polished version of slides and activity script, and do a 60-minute mental run-through.
Same with a lot of other tasks. Some are short but need multiple sessions, like writing recommendation letters that will be closely read. Even though it's easy to write the 2 pages in about 30 minutes, it rarely gets the right tone, and needs at least one or two more 20-minute sessions to capture the applicant's character as clearly as possible.
A task that took three 1-hour sessions is often not doable in one 3-hour session, because you lose creative productivity after a bit of time. That was my first mistake when trying to estimate how long things would take.
Instead, now I calibrate based on time as well as sessions, so I know preparing a new 80-minute lecture (for a class) takes two 5-hour sessions: the first 5-hour session to outline the class and activities, gather the major sources and bullet points I want to make; then the second 5-hour session to put together the polished version of slides and activity script, and do a 60-minute mental run-through.
Same with a lot of other tasks. Some are short but need multiple sessions, like writing recommendation letters that will be closely read. Even though it's easy to write the 2 pages in about 30 minutes, it rarely gets the right tone, and needs at least one or two more 20-minute sessions to capture the applicant's character as clearly as possible.