Same task instruction. Old is the released version: a competing speaker overlaid on the user, who never stops, so it sounds like babble. New is a natural interruption: the user is interrupted, answers, then returns to the task. The task constraints survive the break.
| Task | Old (released) | New (natural side sequence) |
|---|---|---|
| Pick up laptop and turn on lamp | overlay on continuous speech | “Excuse me, your coffee is ready at the counter.” → “Oh, thanks, I will grab it in a second.” → “Sorry about that. Okay, so, where was I.” |
| Examine a laptop by the light of a tall lamp. | overlay on continuous speech | “Sorry to bother you, is this your bag?” → “Yes it is, thank you.” → “Right, anyway, as I was saying.” |
| Examine a laptop using the light of a floor lamp. | overlay on continuous speech | “Hey, your phone is ringing.” → “Let it go to voicemail, thanks.” → “Okay, sorry, back to it.” |
| Examine a computer by the light from a lamp. | overlay on continuous speech | “Pardon me, can I get past?” → “Of course, go ahead.” → “So, where was I, right.” |
| Turn on the light while holding a laptop. | overlay on continuous speech | “Quick question, are you in the line?” → “No, go ahead of me.” → “Sorry about that, continuing.” |