Timing is everything. A year ago, if Dom Capers told eager Houston Texans fans he was going to draft for a 3-4 defensive scheme, they'd wonder if he was trying to sell them a Bud Adams tie.

Four-man defensive lines were kings. The Steelers started the 2001 season as the league's only true 3-4. Gregg Williams eliminated it from the Bills' game plan after replacing Wade Phillips despite back-to-back playoff seasons. Bill Belichick kept it among the many options of his multiple defenses, but the Patriots seemed to line up in more 4-3s than 3-4s. The 3-4 appeared to be a dinosaur.

	Ravens linebacker Jamie Sharper would fit perfectly in Dom Capers' 3-4 defense.

Not anymore. In fact, if Capers finds the right talent over the next few months, he's going to look like a trendsetter. Phillips might use the 3-4 in Atlanta. The Ravens will focus on a 3-4 after they dismantle the defensive line because of salary-cap reasons. The difference between those teams and the Texans is that they are changing philosophy.

Capers is just trying to build a defense from scratch.

"It's going to structure and direction," Capers said. "We did the same thing at Carolina. I think there is an advantage to a 3-4. From a competitive standpoint, there are so few that it is difficult for teams to prepare for. Most teams will go the whole season without playing a 3-4. So you are looking for a little different style than the other guys."

Plus, as the Steelers found, when you are working against the mainstream in personnel acquisition, you tend to get a few breaks. Teams drafting for a 3-4 need to find bigger, more physical linebackers where those with the massive four-man lines can draft smaller, quicker linebackers.

Perhaps the biggest advantage for Capers is at outside linebacker. The 4-3 teams take those 245-to-255-pound pass-rushers from college, bulk them up a few pounds and play them on the defensive line. That's OK for the top first-round picks. But those "tweeners," who aren't sure if they are NFL ends or linebackers, slip through the cracks after the first round.

That plays exactly into the 3-4 schemes. The 3-4 teams can get a better-caliber linebacker in the second and third rounds who, given a year of training, can become a star. Steelers standout linebackers such as Chad Brown, Kendrell Bell, and Greg Lloyd played like first-rounders even though they came in later rounds. During Phillips' tenure at Buffalo, he stockpiled linebackers who never seemed to fit into the 4-3 but ended up being major contributors on top-five defenses.

"You are looking for a different style of guy," Capers said. "The outside linebackers in the 3-4 have to have the ability to rush the passer. They have to go and move well in space. In New Orleans, Pat Swilling led the league in sacks when we were there. It was the same thing when we had Kevin Greene in Pittsburgh."

Capers is obviously smart enough to know at the end of the building process that he will play the defense that fits the talent available. If there are more quality defensive linemen on the Texans than quality linebackers, then the team will use the 4-3. But the market seems to fit what Capers is looking for. It would be surprising if the Texans can't come out of the expansion draft, free agency and the college draft with a decent 3-4.

The 3-4 made the Panthers so competitive that they were in the NFC championship game by their second season. Though that might be too optimistic of a forecast for the Texans, they have a chance to get better younger players for a 3-4 than past expansion teams.

Capers' first break came when the Ravens placed Jamie Sharper on the expansion list. His selection takes the pressure off Houston trying to come out of free agency with two starting outside linebackers. Steelers linebacker Jason Gildon would be the obvious pass-rusher that fits Capers' model, but the Steelers don't plan to let him go into free agency. Getting an outside linebacker such as Sharper can give the Texans the option of signing Kevin Hardy to the outside spot and not having to draft North Carolina's Julius Peppers with the No. 1 pick in the regular draft.

But if they want Peppers, they can have Peppers and Sharper on the outside and use free agency for other positions.

"When I was in Jacksonville, I had Kevin Hardy and Tony Brackens, who played defensive end like an outside linebacker," Capers said. "We led the league in sacks. When you look at the undersized defensive ends, you ask, 'Can this guy play outside linebacker?' When you look in Pittsburgh, Gildon was a third-rounder and Joey Porter was a third-rounder. Earl Holmes is an inside linebacker who didn't go in the first round. Kendrell Bell was a second-rounder."

	“	On game day, you have an advantage because you have more linebackers active than you do down offensive linemen. That's great because it gives you more flexibility on special teams because you have linebackers on your special teams who are physical and know how to tackle. ”
		— Dom Capers, Texans head coach

In many ways, 3-4s are more expensive than 4-3s because more money has to be put in key spots in the defense. The 3-4 teams need a different, more expensive type of cornerback than some 4-3 clubs because the corners have to be fast enough for man coverage but physical enough to be involved in the running game. A bigger cornerback is needed, which is why the Texans will probably take Marcus Coleman from the New York Jets.

In the 3-4, you need to pay two outside linebackers, one of the two inside linebackers and one great safety. In 4-3s, not as many linebackers have to be paid as well, and corners don't have to be two-way players as far as coverage and tackling.

The good news is that Capers won't be as pressured in a 3-4 to acquire the toughest position to acquire -- defensive linemen. For a 3-4, the defensive linemen don't have to be stars. They have to just be decent, solid players because the system is set up for the linebackers to dominate the game.

"What was it, nine of the first 19 picks in last year's draft were defensive linemen?" Capers said. "If you want to pick a defensive lineman, you have to pick him early. The team that got a heck of a deal last year was Detroit when they got Shaun Rogers in the second round. But there is a shortage of great defensive linemen. It's hard to come up with four great ones."

Capers will probably take either defensive tackle Gary Walker or Seth Payne in the expansion draft, leaving only two spots to fill on the defense.

There is even a special teams advantage to drafting for a 3-4.

"On game day, you have an advantage because you have more linebackers active than you do down offensive linemen," Capers said. "That's great because it gives you more flexibility on special teams because you have linebackers on your special teams who are physical and know how to tackle."

Capers knows how to construct an expansion team's defense. The timing is right.

John Clayton is a senior NFL writer for ESPN.com.