Once More with Feeling
summary
Claim: perceived speed matters more than raw bytes. Users feel anything over 100 milliseconds and revenue moves — Amazon/Walmart report ~1% gain per 100ms saved. Concrete techniques shown: use preconnect/preload and pre-render wisely, inline critical CSS, async/defer scripts, service worker app shell and skeleton screens. Wired case study: inlining critical CSS plus async JS and font loading cuts first meaningful paint by about nine seconds on 3G. Also: deliberate micro‑delays can increase trust for complex flows.
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chapters (15)
- 0:00Introduction to perception
- 2:43Brain manipulation examples
- 5:55Digital interface delays impact
- 7:18Web request performance breakdown
- 9:43Performance trade-offs and costs
- 11:07Elevator mirror solution analogy
- 13:34Active vs passive waiting
- 15:18Resource hints and preloading
- 19:47Browser critical rendering path
- 22:56JavaScript and CSS optimization
- 24:42Critical CSS inlining benefits
- 25:44Progress bars vs skeleton screens
- 28:53Progress feedback and anxiety
- 31:21Faster isn't always better
- 33:07User-centric performance focus
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