Timed Talk

Timed talk

A talk with a fixed slot is not a document that happens to be spoken. The clock is the design constraint, and it binds before content, structure or visuals do.

Three ideas carry the whole skill:

• The script is the deliverable. Slides are the visual aid. Write the words first.
• The budget is arithmetic, not judgement. Words ÷ rate = minutes. Compute it, then measure the draft against it.
• Cut by design, not by acceleration. Mark what can be dropped before you need to drop it.

Time arithmetic

Do this before writing a word, and show the numbers.

• Delivery rate under stress: 130 words per minute. Nervous speakers accelerate; planning above 140 is planning to be unintelligible.
• Target 90% of the slot. Fifteen minutes means a 13.5-minute script. The buffer absorbs a slow start, a projector fumble, and one lost thread.
• 13.5 min × 130 wpm ≈ 1,750 words.
• One slide per 50–70 seconds. A 15-minute talk is 12–16 slides, not 30.

Write the per-slide word budget into a table before drafting.

Measure, never estimate. A word count you eyeballed will be wrong, and the error runs to whole minutes — long enough to lose the ending. scripts/check_timing.py reads the script and reports actual counts per slide and overall. Run it after every substantive edit, and report what it returned rather than what you expected.

Script convention

The spoken words live in the script file as blockquote lines, which is what check_timing.py counts:

## Slide 7 — Architecture
**Time:** 1:15 · CORE

> Everything you just saw runs through one chain.
> A source, three transforms, a destination.

CUE: click to reveal the second column
NEXT: "That chain only works because of one decision…"

Everything outside the blockquote is stage direction and costs no clock.

Spoken-script style

• Sentences under 20 words. One clause per breath. If you cannot say it in one breath, split it.
• Use contractions. "It doesn't scale." Written-formal read aloud sounds like a hostage statement.
• Say numbers the way a person says them. "About a third of requests," not "31.7%." Precision belongs on the slide; the mouth rounds.
• Signpost before enumerating. "Three decisions shaped this. First…" The listener cannot see your outline — give them the shape before the content.
• Chain, don't nest. Written prose nests subordinate clauses; speech chains short sentences. Turn "which, because of X, meant Y" into two sentences.
• Expand every acronym once on first use, including the obvious ones. There is always one person from another specialism.
• Write the transitions. The sentence carrying the audience from slide 7 to slide 8 belongs in the script. Improvised transitions are where time disappears.
• Draft in the language of delivery. Translating a script kills its rhythm.

The mouth carries the verb, the slide carries the noun. Any sentence that is both on the screen and in the script is a sentence the audience finishes before you do, and then stops listening.

Timing control

• Mark every slide CORE or CUTTABLE, aiming for 20–25% cuttable. Running long, the speaker drops a marked slide. Speeding up destroys comprehension and is the reflex to design out.
• Protect the graded content. Whatever the talk is being judged on — the problem, the results, the ask — stays CORE.
• Put a wall-clock checkpoint in the middle slide's notes. One glance tells the speaker whether to cut.
• The demo is the biggest timing risk. Play a recording, pre-trimmed to the budgeted seconds, and keep two stills in reserve. A speaker fighting a video player for ninety seconds loses those ninety seconds permanently.

Slide layout

Projector-safe and back-row legible. Conservative on purpose: a timed talk is a bad place to discover that a visual choice does not survive the room.

• One idea per slide. If the title needs "and", it is two slides.
• Body ≥ 24pt, titles ≥ 32pt. Smaller is invisible past the third row.
• Six lines, six words a line. Fragments, not sentences.
• High contrast, and assume the lights stay on. Dark on light survives a bad projector; light on dark often does not.
• Encode meaning in shape, label or position as well as colour. Roughly 1 in 12 men has a colour vision deficiency and audiences are small enough that the odds are not on your side.
• Regular or medium font weights. Thin weights disappear under projection.
• Fix the title position across every slide. A title that shifts 20px reads as carelessness even when nobody notices it consciously.
• Figures beat tables; tables beat paragraphs. More than 4 rows or 3 columns means a figure.
• Number every slide. Someone will say "go back to slide 9."

Workflow

1. Read the whole source pile before structuring. Report, notes, recording, prior decks.
2. Establish the constraints: exact slot, language, who is in the room and how technical, whether a template is imposed, whether the demo is recorded, whether questions follow.
3. Produce the time budget and slide plan — title, one-line purpose, CORE/CUTTABLE, word budget. Get approval before writing prose. Done when every slide has a row.
4. Write the full script as a standalone markdown file. This is what the speaker rehearses from, so it ships even when the deck does.
5. Run scripts/check_timing.py and cut or expand until it reports the script under target. Done when its output says so.
6. Build the deck, script into the speaker notes, verbatim.
7. Deliver both files. A speaker rehearsing from a deck cannot see the notes and the slide at once; a printable script solves it.

Generate the deck from the script file rather than typing notes twice — a deck and a script that drift apart are worse than either alone, and by the last rehearsal only one of them is true.

Variants

The machinery above is the same for every timed talk. What differs is the section structure, what the audience is listening for, and how questions work.

• Academic defense (soutenance, PFE, thesis) — references/academic-defense.md
• Conference talk — references/conference-talk.md

Read the one that matches before producing the slide plan.

Verification

Report measured numbers, not assurances:

If it overruns, say so and cut. A faster delivery rate is not a fix, it is the same overrun with worse comprehension.