A very small percentage of the fan base likes Spencer (and I assume you aren't in that group) and the group that doesn't, don't seem to want him on the roster under any circumstances, even if he were to sign cheap.
So far starters let me say this. He's 29 and won't be 30 untill deep into the playoffs, and a 5 year deal will run untill he's 33 (34 at the end of the final season). Which doesn't mean we're stuck with him untill he's 34, it only means we're able to spread the bonus out that far and more than likely we can release him at age 31 or 32 if his play drops. That's how contracts are set up in the NFL, nothing specific we're doing, it's what all teams are doing.
And the reason I was such an advocate of Spencer returning is because I once Romo is no longer playing at an elite level, we're done. Whether we have cap space or not, this team will not be good. It only takes a season or two to purge bad contracts and a team that begins the offseason with 10-20 million in cap space, but it takes a lot longer to find a QB capable of leading your team deep in the playoffs. Just look at this team, this year. We're under the cap and could easily be in great cap standing next off season by 1.) Letting Spencer play out the year on the franchise tag and letting him walk, 2.) Release Jay Ratliff and Doug Free now, as opposed to june first, so they count only on this years cap and 3.) Trade/release Tony Romo now as well.
Those 3 moves will likey put us in great cap shape for 2014 and after a few moves in 2015, we'll be even better. But we have no shot at winning in those season. Even with the talented Mr. Ware and Dez Bryant and all the other pieces we have. No shot
So for me, it comes down to the fact that we're a better team with Anthony Spencer, than without him. Can't even debate that. And while I don't think it's likely we win a super bowl before the window closes, I think we need to continue to try. We have an elite QB (or the best non elite QB if you feel like arguing), arguably the best all around TE, one of the better WR duos in the NFL and a LT who has the ability to be a perenial pro-bowler. The rest of our o-line is a joke, but it's not hard to get interior linemen or RTs. On defense, we have one of the better pass rushing duos in the NFL. 2 LBers who have the potential to be pro-bowl level players (3-4 OLBs always get most of the spots though) and a CB duo that has the potential to be one of the best in the league. Our interior needs a ton of work here as well as well as the saftey position, but these or not positions where it's unreasonable to think we can get 2-3 starters in the draft alone. The time to go all in is now, consequences be damned, because at the end of the day, when Romo is done, we're done.