Why can’t the Celtics shoot? Shooting guru Dave Hopla has some thoughts.

With all that’s ailed the Boston Celtics along this season of uncertainty, from injuries and execution, to coaching and a lack of caring, the three-point line has been a particular pain. At a time when long distance shooting is more valuable than ever in the NBA, the Celtics continue to struggle.

Through 38 games this season, after Wednesday night’s loss to San Antonio, president Brad Stevens’s crew ranks 24th overall in three-point percentage. At .333, Boston’s current rate is its worst since the 2013-14 season (when Kris Humphries and Gerald Wallace ruled the roost), and a far cry from the 2017-18 season, when Boston boasted the second-best three-point percentage (.377) in the entire…