i think Sean left the Saints because they chose Drew over Tom who Sean had heavily recruited. Imagine if you had worked hard to get one of the greatest quarterbacks of all time to join your team only for the incumbant to come back in last second because he didn't want it to negatively affect his legacy. i think in the end, the Saints lost, and Drew won. Now we will forever live in Drew's shadow while Sean goes on to get riches and glory. This falls on Mickey and Gayle for choosing an aging Drew Brees over Tom Brady. Drew ended up losing to Tom and throwing 4 interceptions in his final game as a Saints. Furthermore, this broke Sean's heart and now he is in Denver smoking bongs.