Ines wrote back on her own pad: 'The lab logs every power spike. Check the computer.' Mara pulled up the file. There it was, the exact moment the coil sang too high. A reverse setting was listed, grayed out, marked 'requires two synced operators.' They couldn't sync. That was the whole problem.
Mara realized 'two synced operators' meant pressing the reverse button at the exact same real moment, not the same clock moment. She wrote out a countdown plan and held it up for Ines: 'When my note says GO, count five, then press.' The two-minute lag would line them up.
Mara wrote GO and started her count. Two minutes later Ines saw it and counted too. Their fingers came down on the reverse button at the same real instant. The coil pulled the fold inside out, gentle this time. The number dropped straight to zero. The sisters gasped at the exact same second.