Corporations must reckon these days with the need to act during a crisis at social media’s often breakneck accelerated pace, as evidenced when The Walt Disney Co.’s ABC Inc. took only hours to cancel Roseanne Barr’s television show after a racist tweet by the controversial actress and comedian.

Clients must also abide by regulators’ new demands that the public be notified within 72 hours about data breaches. What used to take days of executive decision-making now gets crunched into minutes. To prepare for such fast-moving crisis management, companies and law firms are engaging in what’s known as “tabletops,” a day- or days-long planning and drilling sessions.