"You may not be too late to a play," says Trevor Rees-Jones, founder of Chief Oil & Gas, whose Barnett shale E&P assets were sold in 2006 for $2.2 billion to Devon Energy Corp. Its Barnett midstream assets were sold separately for $480 million to Crosstex Energy LP.

"We thought we were six months too late to the Barnett but it turned out we were very early. Now it'll be interesting to see how far out it really goes. I predict it will extend further than any of us now believe."

Rees-Jones had looked at the Barnett since the 1980s, when he entered the E&P business and left his law practice. "It was too risky, we thought, with questionable economics," he told attendees at the second annual Developing Unconventional Gas conference sponsored by Hart Energy Publishing LP recently in Fort Worth.

In the mid-1990s, Chief entered the play. At about that time, Mitchell Energy & Development Corp. was cracking the Barnett code after some 16 years at work at it. Was Chief too late in the play? Clearly not. Antero Resources, whose Barnett assets were bought by XTO Energy Inc., was considered an early player; Chief's involvement even preceded that, Rees-Jones notes.

A unique approach is needed to go after unconventional resources, he advised attendees, who numbered some 700 E&P and finance professionals. "If you're going to go to an unconventional reservoir, you have to leave a conventional mindset behind.

"In the Barnett, in addition to the technical skills you need, you now need good diplomatic skills-and you need time. Unfortunately in the frenzied Barnett, time is something we don't have because lease owners expect drilling to occur right away."

The story of his company's growth ought to be a point of encouragement to small independents, he says. "Very little happens in this industry without perseverance."

Rees-Jones' Chief continues to hold some Barnett assets, and is involved in exploration in Utah now and in the Woodford shale in Oklahoma.

"I can recall many times when the oil and gas industry tried to give me the knock-out punch." Rees-Jones and other operators in the play never dreamed it would turn out to be as prolific and as widespread geographically as it is today, producing close to 2 billion cubic feet of gas per day from some 20 counties.

"I would hate to fathom where the U.S. would be if all we had to do is conventional gas drilling. It's exciting to think we're on the front end of this new era. The Barnett shale is a good laboratory for all the other shales in the country."