I think your final statement describes the Moss situation, but I'm not so sure it applies to Maroney and Seymour.
Maroney isn't a very good RB, and since the Broncos were willing to give up a 4th round pick for him, it was time for the Pats to let go of someone who never quite lived up to his potential.
Seymour on the other hand was still a very productive player, and would have commanded a fairly large salary. But, the Raiders were stupid enough to dump a 2011 1st round pick for him. It doesn't matter who you are, a first round pick for an aging DE with a huge salary is a trade you do without much thought.
Well, the rumors around here are that Maroney's work ethic sucks which is why a far less talented player (BJGE) passed him on the depth chart. Supposedly last year's sit-down sessions with BB were forced on him and he basically expected that because he was talented and good in college, he could do the bare minimum and be good in the pros.
I don't think he had a shitty attitude beyond that, but his lack of work ethic must not have been a locker room booster.
What you said about Seymour is definitely true. The Pats jumped at the opportunity simply because of what was being offered.
So, I stand partially corrected on Maroney and corrected on Seymour, but my cleaning house point still stands (I think). Moss, Maroney, Merriweather being benched, TBC being benched, Thomas (last year) benched and cut... Pats are trying to build what they had in 01-06 again.
As for Moss, I just heard that a condition of the trade is that the Vikes have to extend him. THAT makes a lot more sense. If Moss walked at the end of the year, particularly as a malcontent, where do you think he'd LOVE to go and what team would LOVE to have him? Sexy Rexy and his Gangrene?