#2. To not derail Roman Reigns' momentum as a solid babyface
There's absolutely no denying that Roman Reigns deserves all the adulation and respect in the world for overcoming his despairing battle with Leukemia.
While the WWE Universe have embraced The Big Dog's return to the squared circle, the fans could turn their backs on the former Universal Champion if he continues to be portrayed in superheroic fashion.
With Seth Rollins and Dean Ambrose always being the backbone of The Hounds of Justice, Roman's inclusion in the frame would keep him protected and cheered on the Road to WrestleMania 35.
Since Vince McMahon will look to ascend The Big Dog back to the top, it seems like the company would be more cautious than ever now, and would probably advocate the idea of gradually propelling him back to his position.
Therefore, The Shield's reunion would play a very indispensable role in keeping the spotlight on Roman Reigns and not derail his momentum heading into WrestleMania 35.