MIAMI — This column planned to frame Tyler Herro as the X-factor to the Miami Heat’s play-in game and, thus, its season. The idea was to look at Wednesday’s play-in game in Philadelphia through Herro’s re-arrived offense. It was to say his re-emergence from this latest injury is what this point-challenged team needs. But then Heat coach Erik Spoelstra looked down to the other end of the court Tuesday afternoon where the last player still practicing, Jimmy Butler, was shooting free throws.