It is not the fact that Matt Cassell wanted to leave, but rather the fact that he became so successful in the 2008-2009 season with the Patriots.
Putting up an incredible 11 win and five loss season after Tom Brady suffered a season ending injury in the first game of the season was more than expected of the four year back-up quarterback.
Because of Cassell's success, he was a prime pickup for any team lacking in the quarterback position once the Patriots placed the franchise tag on him. The Kansas City Chiefs, who later extended his contract to more than $60 million with a guaranteed $8 million, were looking for someone like Cassell to help revive their franchise.
Why rid New England of such promising talent?
The simple answer is the return of the chosen one, Tom Brady. After a grueling months in rehab, he has been working with trainers in an attempt to re-establish himself to his pre-injury condition.
With three Super Bowl wins in four trips, there wasn't a doubt that Brady would return to the field once the Patriots decided to send Cassell away.
Cassell was a type of insurance policy, intended to keep a solid pocket presence in case a season-ending injury turned into a career-ending affair.
With Tom Brady back on the practice field and feeling better than ever, it is highly likely that we can expect to see the Patriots maintain their caliber of play, even if there may be a few new faces taking up slots in the lineup.