When people think of Ben Affleck they tend to focus on his acting and directing career, but he's also an accomplished screenwriter, having co-written The Town (2010), Gone Baby Gone (2007) and, of course, sharing an Oscar-win with Matt Damon for the Good Will Hunting (1997) screenplay. So if Affleck decided to tinker with the Batman v. Superman: Dawn of Justice script, it's a bonus!
A source for US Weekly says Affleck “would go into wardrobe and get all suited up for the day in his Batman suit,” and then "he would sit around reworking the script.”
Does that sound possible? Sure. However, their source also mentions that Affleck "wasn't thrilled with the script and would find himself on multiple occasions fixing it the day of.” That's a bit hard to swallow, as the script was penned by someone he has the utmost respect for, Chris Terrio, who won the Academy Award for Best Adapted Screenplay for 2012's Argo, which Affleck directed and starred in.
In Batman v. Superman: Dawn of Justice, fearing the actions of a god-like Super Hero left unchecked, Gotham City’s own formidable, forceful vigilante takes on Metropolis’s most revered, modern-day savior, while the world wrestles with what sort of hero it really needs. And with Batman and Superman at war with one another, a new threat quickly arises, putting mankind in greater danger than it’s ever known before.
Batman v. Superman: Dawn of Justice opens March 25, 2016.