While Kevin Durant and his Oklahoma Thunder team are immensely talented, they will probably not win a championship while he is on the team. Since 1970 when the NBA started keeping track of scoring titles only 3 have won NBA titles while leading the league in scoring.
Those three are Kareem Abdul-Jabbar (71') Michael Jordan (91-93,96-98) and Shaquille O'Neal (00'). Generally the teams with the leading scorer rely to heavily on that person to get the job done creating a weaker team overall around that athlete.
The Thunder currently have two of the top scorers in the league, Durant leads all scorers while the injured Westbrook scores 21.2 PPG.
Even though Durant does dish out more assists than more scoring champions usual have his Thunder will not win a title without Westbrook and another player who averages closer to 20 points per game.
Have a good Sunday!