User blog comment:Theultimatesorafan/Anyone having problems with Red Dead Redemption Multiplayer?/@comment-97.91.183.42-20140419015124

This is the reason why:

http://reddead.wikia.com/wiki/Forum:Red_Dead_Xbox_platform_lagging

Simply put, a Malicious group of Modders led by a Player called GLITCHED MATRIX is responsible for the problems afflicting Red Dead Redemption currently. They did this once before in August as well, Rockstar Patched that issue back in November.