The release of Love and Deaderick attests more to the weakness the Defense had at that position the past few seasons, than anything else.
Lets take a little jaunt down memory lane, shall we?
The year was 2011, there was an obvious need on the D-line for new talent, there was as much need there as anywhere on the roster. I had very interesting debates about that during the offseason that year, but few wanted to see the glaring need we had there...
So they went into TC in 2011 with Marcus Stroud (signed after the Bills waived him, he never played a game for the Patriots and retired before the season began), Ty Warren (who had been one of the walking wounded for two seasons, and hadn't played solid football for the Patriots in a long while), Mike Wright (who in 2010 had suffered one of the worst concussions I had ever heard about, six months after the concussion that landed him on IR he was still having headaches, and having trouble with bright light), Gerard Warren (who was very long in the tooth, and had no tread left on his tires),,, and players like Kyle Love, Brandon Deaderick, Ron Brace and Myron Pryor guys that wouldn't have made the roster if not for the fact that the four guys I mentioned before them were off the team or IRed by the end of week 1.
The Patriots, realizing the problem early on, made a trade for Albert Haynesworth, who they tolerated on the team until they got Deaderick and Pryor back from PUP near mid-season, and then they dumped him.
In 2012, they still did not bring any big names in for the DT position, not in the draft or FA... though they did add Marcus Forston, Justin Francis, Trevor Scott and Chandler Jones, shoring up the DE positions.
I think you could say, Pryor, Love and Deaderick may have taken steps back in 2012... from their 2011 production, they certainly did not make any big leaps forward.
So here we are in 2013, the Patriots have brought in Tommy Kelly, Armond Armstead, Dewayne Cherrington, and Cory Grissom... all in the 300 to 335 range... so they are all here to play DT. Joe Vellano who is 6'2 and 285 may also be in that mix, though he is on the light side compared to the rest.
They also have Marcus Forston (310) now in his second season, who is in the mix, and who I give an edge to over Vellano and Grissom.
So the Patriots STILL have 5 or 6 guys on the roster, who will be competing for probably 3 roster spots, and as we all know Vince Wilfork will be the #1 DT. So there will likely be Wilfork, Kelly, Armstead and Cherrington ... should an injury happen, and someone is IRed or PUPed, that makes room for Grissom or Forston or some as yet unknown FA to make the roster.
The Patriots simply moved forward to the conclude things with Love and Deaderick that were highly probable to happen anyway, long before the season began.
In the case of Love, it was practically a foregone conclusion, as players like Cherrington and Forston have contracts for probably half of what Love was getting paid, and they have another 3 years or so on the roster with the Patriots, where as Love would have been a FA after this season... cutting Love now had teams scrambling to pick him up off of waivers, so they pick up his contract.
Take five minutes to look at who is still on the roster at the DT position, and consider this is far more of a 4-3 Defense now than a 3-4... which means instead of playing 3 DTs they will only be putting 2, sometimes only 1 out there... and its obvious they still have plenty of depth at the position heading into camp.