The 68-year-old, who has built a career striking more than 500 deals in sleepy industries such as garbage collection and supply-chain logistics, has become an unlikely guru in M&A circles. He does a lot of the things familiar to any Wall Street takeover artist, like hunting down targets, turning up the pressure to clinch deals and slashing costs while rolling up businesses. But he wraps those tactics in a much different package, bringing an effervescent, feel-good vibe to a world known for ruthlessness and no-nonsense finance speak.