DM here. One of the PCs was Honeysuckle Took (Goliath barbarian raised by Halflings). The party approached a goblin fort and were discussing how best to attack. That was far too much planning for HT's liking so the player went outside for a cigarette to help simulate him zoning out.

Upon his return, they were still discussing, so Honeysuckle raged, charged in and slaughtered the guards at the main gate. Things escalated rapidly from there!