Blackstone announced on Tuesday that Jon Gray would become its president and chief operating officer. : Blackstone may think of itself as a disruptive investor, but its approach to succession planning is anything but. The giant alternative-investment manager named the head of its real estate business, Jon Gray, as its day-to-day manager on Tuesday, shunting Tony James into a vice chairman role. Big questions — like whether to remain a partnership — will still sit with the chief executive and co-founder, Steve Schwarzman. Blackstone isn’t run for outsiders’ benefit, and the gradual approach to change shows it.