I hate to be "the glass if half empty", but that contract doesn't mean anything if he doesn't make the team after training camp. Same goes for Gerald Riggs, etc. However, I think Gaither can make the team. At that level, it's about the determination to out work the guy next to and across from you.
The guys that last the longest in the league (excluding rare talent or hype) are the guys that take the job seriously and stay healthy.