Is Nets team president Rod Thorn out of his mind? It looks like the Nets finally found a competent big man in Mikki Moore and now they are going to risk letting him slip away via free agency.

Moore was one of the Nets’ feelgood stories of the season. A veteran journeyman who had sat at the end of several NBA benches despite solid per minute production, Moore joined the Nets last summer and began the season on the periphery of their rotation. However, his burn increased as incumbent center Jason Collins proved ineffective following several knee surgeries, and when Nenad Krstic went down for the season before the holidays, Moore stepped into a starter’s role and did well. He averaged 14.9 points and 7.7 boards per 40 minutes of action, and there’s no telling how many loose balls he grabbed with his scrappy play. In the playoffs, Moore stepped it up and nearly saved the Nets’ season with a heroic Game 4 against Cleveland in the conference semifinals when he notched 25 points on a sizzling 11-of-14 shooting.

Moore’s emergence last season as well as that of Bostjan Nachbar, another journeyman who finally found his footing in the league, argued that the best NBA benches — like the best major league baseball bullpens — were built rather bought. And with Moore entering the summer as an unrestricted free agent that may be Rod Thorn’s thinking. After a season like Moore’s, many clubs would happily offer him $5 million or $6 million a season, their entire midlevel exception, for five years. Instead Thorn’s most recent offer to Moore, who made just $1 million and change last season, is three years and $10 million.

But Thorn hasn’t lost his mind. Work with me for a second.

Moore turns 32 in November, and while big men retain their value longer than players who rely on their speed and agility, 32 is still old in NBA years. At end of the deal the Nets are offering, Moore will be pushing 35 and almost certainly in decline. Moore’s age also works against him in that this isn’t a young player finding his NBA groove; it’s an older player having a peak season. He’s unlikely to repeat last season’s performance since it’s completely out of whack with his other nine seasons in the pros. In addition, while Moore has been a productive player, he’s no budding all-star. Last season, his Player Efficiency Rating (John Hollinger’s system for evaluating player production on a per minute basis) is 14.3, right below the league average of 15.

While league average players are a godsend in comparison to the Antoine Wrights of the world, they shouldn’t be that hard to come by — even 7-foot ones. The Nets front office has excelled in knowing when to cut bait. Their decision not to re-sign Kenyon Martin now looks like pure genius in light of K-Mart’s injury troubles in Denver, but he had some injury woes in New Jersey, too, and even when healthy, he was a 16-points/8-rebounds a game player. That’s not what you spend $13 million for seven seasons on. Thorn also picked the right time to drop Kerry Kittles and Luscious Harris.

Teams often fall in love with their own role players and overpay them, which is what gets them into cap trouble. The Lakers recent six-year/$30 million contract with Luke Walton is idiocy in its length. At 33, Walton won’t be half the player he is now. Superstars should get the maximum amount of money and length possible. After all if you can have LeBron James, Dwayne Wade, or Kobe Bryant on your team then you should spend everything possible to do so. With Mikki Moore-type players, a more nuanced strategy is in order.

In this regard, it’s easy to see what the Nets were thinking with their gamble on Boston College’s Sean Williams in last month’s draft. Williams and last year’s firstrounder Josh Boone are, with Krstic, the Nets future interior presence. If Moore can be added to that mix at a reasonable price, then so much the better. If he can’t be, then the team is covered and can spend its mid-level exception on some backcourt depth.

Thorn is in a difficult position. Jason Kidd is 34 and won’t play at an all-star level forever, and New Jersey’s hopes of returning to the Finals hinge on building a solid team around him while he’s still playing in something resembling peak form. Overpaying for veterans who have an uncharacteristically good season in the walk years of their contracts is standard operating procedure in the NBA, but it’s also a panic move. Thorn’s offer is a shrewd one, and maybe Moore will take it in order to be a member of the rotation on a winning team where he’s a crowd favorite. Or maybe he’ll bolt. Chicago, another winning team, and Memphis, are said to be offering something closer to Moore’s asking price, and he’ d be a good fit on either team. Either way, the Nets are showing in these negotiations that they understand the concept of replacement value in building a supporting cast for their trio of stars, Kidd, Richard Jefferson, and Vince Carter.

The Nets have a good plan, but good plans don’t always work out, as was the case with Jeff McInnis, who bombed as a reserve point guard two seasons ago. But the alternative, bad plans or no plan at all (see Timberwolves, Minnesota) almost never work.

mjohnson@nysun.com