They are so used to being right and having quick answers that they don't even realise when they're making a mess by answering without thinking things through.
他们是如此习惯于正确并拥有快速答案,以至于他们甚至没有意识到当他们不经过仔细思考就回答而把事情弄得一团糟的时候。
由 "that" 引导的结果状语从句,与主句的 "so" 构成 "so...that" 框架,表示 "如此...以至于..." 的结果关系。从句主干是 "they don't even realise",后接 "when" 引导的宾语从句说明未意识到的内容。