Protecting the franchise from what though? How is Reynolds playing Deadpool going to effect Green Lantern in any way? Positive or negative? Two completely different characters, two different universes. In Deadpool you wouldn't even see the guys face for 99% of it. Both movies would be coming out in different years. There is absolutely no rivalry there.
At the end of the day they are jobs. He has a contract with Fox and WB. WB doesn't control the guy. Like i said earlier, it isn't one of those "golden handcuff" type deals. Reynolds signed a contract with Fox when he did the Wolverine movie. And you can bet your life savings that there was a sequel/spin off clause in the contract. Fox maybe *******s, but they ain't stupid. And if Reynolds didn't have a contract with Fox, why would they allow him to work on the script and mention the film in pretty much every interview he has done in the last year?
Why should Deadpool be a direct to DVD movie? He's a far more pyschologically complex and compelling character than Hal Jordan. Hal Jordan just has the benefit of being in a sci fi/adventure mythos and a film that is an effects driven event movie. But when it comes to the actual personalities of each character, for me, Deadpool is far more interesting and unique.
And I ain't being funny, but I and pretty much everyone i know finds the idea of a psychologically messed up mercenary who breaks the fourth wall and satirizes Hollywood and comic books far more interesting than some guy who has a "magic ring" that shoots green things whilst reciting some cheesy as hell "oath". I mean come on, anyone who doesn't know the character and is older than 10 is gonna cringe or roll their eyes at the oath. Green Lantern isn't a guaranteed success, and you would be deluded to think it is. You say if Deadpool bombs it'll negatively effect GL, which i don't think would happen if Deadpool bombs anyway. Well what if GL bombs? It is in no way a guaranteed success. That's why i believe this sequels filmed back to back talk is BS and is just trying to force Reynolds into a awkward position.(BTW i like the GL mythos, i'm just speaking from a general audience members POV)