From the boardroom of Flynn O’Driscoll’s Mount Street offices, managing partner James Duggan is ruminating on the germ of the law firm’s recent merger with Vincent & Beatty. “It was fortuitous, really. It was a conversation with a former student I was in a leadership college with,” he says. “He just mentioned the opportunity and asked — would I be interested.” A conversation led to another conversation, then a series of conversations with Vincent & Beatty, a 150-year-old boutique corporate practice in Dublin. For Duggan, heading up Flynn O’Driscoll, a leading mid-size practice with offices in Dublin, Galway, and Shannon,…