Sentence:  Allen Gregory DeLongpre: Pat, I gotta tell you, you did a lot of things right with this lunch―kudos. You got back quickly, you showed initiative, and, best of all, you left plenty of room for improvement. <WSD>Piggybacking</WSD> on that last part, the ugly business of the critique. 
Meaning of the word marked with <WSD> tags:  To attach or append something to another (usually larger) object or event.