The research, and the arithmetic

Your meetings don't cost what your calendar says they cost

Four half-hour meetings take two hours out of your day. Where you put them decides whether the rest of it is worth three hours or five.

Part of you stays in the last meeting

In 2009 Sophie Leroy, then at the University of Minnesota, published a paper titled Why is it so hard to do my work? She was studying what happens in the minutes after you switch from one task to another. The effect is called attention residue.

When you leave a task, a portion of your attention does not leave with you. It stays behind, still working the previous problem, and it degrades your performance on whatever you turn to next. Residue is strongest when the previous task was left unfinished or unresolved. Most meetings fit that description.

A meeting costs you the half hour it occupies. Then it costs you the tail it drags into the time afterwards. Then it costs you whatever it did to the shape of everything around it, and that third one is usually the largest.

Nobody prices it.

Let's do the arithmetic

Suppose your workday runs 9:00 to 5:00, which gives you 480 minutes. You accept four meetings at thirty minutes each. That is 120 minutes booked, so the naive reading of your schedule says you have 360 minutes left to do your actual job.

Two assumptions get us closer. Both are estimates rather than measurements, and you should adjust them if your work demands it. The conclusion holds across a wide range of values.

Residue: 15 minutes

The first quarter-hour after a meeting is spent arriving. You are present. You are not yet useful.

Floor: 60 minutes

A block shorter than an hour does not survive contact with real work. It becomes email. We will not count it.

Day A, scattered

Meetings at 9:30, 11:00, 1:30 and 3:30. Nobody planned this. It is what four separate people's availability produced.

Open stretch	Length	After residue	Usable?
9:00 – 9:30	30 min	30 min	under the floor
10:00 – 11:00	60 min	45 min	under the floor
11:30 – 1:30	120 min	105 min	counts
2:00 – 3:30	90 min	75 min	counts
4:00 – 5:00	60 min	45 min	under the floor
Usable focus time			180 minutes

Day B, stacked

The same four meetings, running from 9:30 to 11:30. Identical commitments, identical people. Only the placement changed. Residue is charged once here, on the way out, because no deep work happens between back-to-back meetings anyway.

Open stretch	Length	After residue	Usable?
9:00 – 9:30	30 min	30 min	under the floor
11:30 – 5:00	330 min	315 min	counts
Usable focus time			315 minutes

135 minutes. Same meetings, same day, same you.

Day B yields 75% more usable focus time than Day A. No meeting was cancelled to get it. That is the part most productivity advice skips past on its way to telling you to have fewer meetings.

Why your calendar produces Day A by default

Nobody in that story wanted a fragmented day. Day A is not a decision anybody made, and fragmentation is not a willpower failure either. It is what a scheduling system outputs when no single view of your time is authoritative.

A work calendar, a personal calendar, a side-project calendar and a booking link are each answering one question: is this slot empty? Not one of them is answering the question that actually decides how your Tuesday goes, which is what the whole day looks like once you say yes, and none of them can answer it, because none of them can see past its own slice of your time. So nothing in the system knows that the 2:00 is the one that wrecks the afternoon. It just sees a gap.

You cannot stack meetings you cannot see.

Four things that actually help

Make one view authoritative

Every calendar you own needs to know about the commitments on every other one. Not so you can read them in one place. So that a slot which is busy anywhere reads as busy everywhere, including on the link you hand to other people.

Publish windows, not days

Offer someone all of Tuesday and Tuesday gets carved into half-hour pieces. Offer Tuesday between one and five and every booking lands inside a region you have already written off. Your morning stays whole. This is the highest-leverage setting on most booking pages, and most people never touch it.

When you get a choice, stack

You are offered 10:00 or 2:00. There is already something at 10:30. Take the 10:00. Spreading meetings out feels like the polite thing to do, and it feels less crowded. The arithmetic prefers them bunched. You are not buying a comfortable morning. You are buying an untouched afternoon.

Give the block a name on the calendar

An empty afternoon on a shared calendar is an open invitation. A named block is a commitment other people's tools have to route around. If your calendars are synced, one focus block defends itself everywhere at once.

The honest caveat

The fifteen-minute residue and the sixty-minute floor are stand-ins. Your real numbers depend on the work. A debugging session needs a far longer runway than a reply to a support ticket, and someone whose job is mostly conversation may carry almost no residue at all.

The shape of the result does not depend on the exact figures. Any model where switching costs something, and short gaps are worth less than long ones, produces the same conclusion. Placement beats count. Placement is also the variable you can usually move. You often cannot decline the meeting. You can nearly always pick the slot.

Start by making one view true

MergeDay syncs your Google and Outlook calendars both ways. A commitment on one of them blocks the time on all of them, and on the booking link you share. Set your bookable windows once, and the meetings other people book start landing where you decided they could.

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Reference

Leroy, S. (2009). Why is it so hard to do my work? The challenge of attention residue when switching between work tasks. Organizational Behavior and Human Decision Processes, 109(2), 168-181.