The Celtics sure have had a confounding journey lately. If you just zoom out and look at their overall statistical profile, you won’t find much to worry about. They still lead the league in net rating. They are the only team in the top five in both offensive and defensive efficiency. Their record trails only that of Milwaukee. The predictive models I usually check, including ESPN’s BPI, Basketball-Reference and Five Thirty Eight, consider the Celtics one of the championship favorites, if not the championship favorite. Advertisement It’s just hard to ignore some of their recent losses. They gave up a…