A compelling story could be written just about 49ers defensive line coach Jim Tomsula cutting firewood.

No. Really.

There is Tomsula’s cutting-firewood-and-snakes story, his cutting-firewood-and-alligator story and the Southern wisdom he received from his coaching buddy Fred Hamilton about cutting firewood around South Carolina’s swamps: Always bring jumper cables (this way, in the event of a snakebite, you can “jump yourself,” which will kill the venom … not to mention all the muscle around the affected area).

Based on his memorable one-week stint as the Niners’ interim coach last year, it wasn’t surprising to discover that Tomsula, “Jim Nobody From Nowhere,” was an entertaining and fascinating feature subject.

But in the process of writing this story about Tomsula, I gained a deeper appreciation for his coaching ability – a gift that’s somewhat obstructed by his self-deprecating humor and just-a-Pittsburgh-guy persona.

Julie Tomsula said something revealing when she mentioned how her husband has refused to hire an agent, “He’ll say ‘I can’t bring myself to pay someone to talk about me. If my work isn’t enough …’”

He’s applied the same philosophy as he’s climbed the coaching ladder, from Division II to the NFL. Tomsula, allergic to glad-handing, was never hired by a friend or former colleague in his four stops in NFL Europe. He earned his positions by word of mouth — you know, man, that guy can really coach.

Then-Niners coach Mike Nolan didn’t know Tomsula before he hired him. But Nolan kept noticing how Tomsula’s players kept returning markedly improved from Europe.

His influence in San Francisco is hard to miss. The Niners, who ranked 16th in yards allowed per carry in 2006, have ranked fourth in that category during Tomsula’s four seasons. They will enter the 2011 season without having allowed a 100-yard rusher in 22 straight games, the longest streak in the NFL.

Stanford co-defensive coordinator Jason Tarver, a defensive assistant with Tomsula the past four seasons, cites Tomsula as a major influence on his career.

Tarver, who earned his master’s in biochemistry and molecular biology from UCLA, has never had much trouble grasping complicated concepts. But he’s learned how to better translate that understanding to his players by watching Tomsula, who he says has a knack for making NFL-level X’s and O’s as easy as ABC.

“Jim has a great way to make complex things sound simple,” Tarver said. “I have spent a lot of time watching him do it and it’s helped me out. His influence is one of the main reasons I was able to get this job. He always puts himself in the players’ eyes and then uses words, diagrams and video to make them understand it.”

Tomsula’s teaching could come in particularly handy if nose tackle Aubrayo Franklin doesn’t re-sign with the 49ers. The Niners didn’t address the position in the draft and could have a serious question mark at what is arguably the most vital spot in their 3-4 defense.

General manager Trent Baalke was asked about the position in his post-draft press conference and jokingly referenced Tomsula in his response.

“After the draft ended, I walked through and told coach Tomsula to get ready,” Baalke said. “He might have to get out and suit up this year.”

Tomsula won’t be making any solo tackles this season, but the Niners could be crediting him with plenty of assists.