What was Mike Garrett thinking?

This question, of course, is based on the large and dangerous assumption that he was actually thinking.

On the contrary, in handing his heavyweight USC football team to lightweight Lane Kiffin on Tuesday, Garrett has seemingly lost his mind.

The USC athletic director’s few remaining defenders have always deflected criticism toward Garrett by claiming he is a true Trojan.

This is who a true Trojan hires?

A program that defines itself by victories over UCLA just signed a guy who was out coached by UCLA’s Rick Neuheisel just four months ago, Kiffin’s Tennessee team losing to the Bruins in Knoxville.

I haven’t yet talked to Neuheisel, but I can guess his two-word reaction to this move.

“Thank you.”

This is who a true Trojan hires?

A program that defines itself in consistency of leadership just acquired a guy who walks out of a Tennessee program after only one season.

If he’s not staying in football’s best conference for one of its best contracts -- more than $2 million a year -- then how much chance does USC have of keeping him long? Volunteers students and fans were so angry at Kiffin’s sudden betrayal, they marched on his goodbye news conference Tuesday night and showered him with obscenities.

Once they calm down and remember that he led them to only a 7-6 record with nearly as many minor NCAA infractions as big plays, I’m sure those Tennessee folks will also have a two-word reaction.

“Thank y’all.”

This is who a true Trojan hires?

A program that covets an NFL pedigree just added a guy who was 5-15 with the Oakland Raiders in his only NFL head-coaching experience.

How bad was that experience? Al Davis ended it by calling him a “flat-out” liar.

Yeah, that bad.

This is who a true Trojan hires?

A program that thrives on the big play just hitched its future to a guy who was holding the controls during this team’s worst play in many years.

It was the Rose Bowl after the 2005 season, the Trojans needed one first down to clinch the win and national title against Texas, it was fourth and two, remember?

USC called a running play with LenDale White plowing straight ahead while Heisman Trophy winner Reggie Bush incredibly watched from the sidelines. White was stopped, Texas took the ball and eventually a game, the dynasty’s downfall began.

The offensive coordinator for that play? Your new USC head coach, Lane Kiffin.

What was Mike Garrett thinking?

Other than, why not hire a 34-year-old former Trojans errand boy who won’t challenge my power or ego?

I mentioned about 86 names of potential candidates in my Tuesday column, but I purposely did not mention Kiffin even though I covered him and liked him during his six seasons here on Pete Carroll’s staff.

He wasn’t big enough. His star wasn’t bright enough. Maybe one day, but not this day, not now, and especially not after his recent past.

When protected by Carroll’s buoyant presence, Kiffin was a smart young assistant. But after he set out on his own, he seemingly devolved into a spoiled kid.

He couldn’t command the Raiders’ respect. He struggled to bring the Volunteers credibility. He led the Southeastern Conference in smack talk, even accusing Florida’s Urban Meyer of cheating, but while his team nearly beat Alabama, it couldn’t match his hype, on or off the field.

On Kiffin’s watch, one of his star freshman recruits pleaded guilty to attempted robbery. On Kiffin’s watch, the NCAA began an investigation into the role of Tennessee hostesses in luring players.

“I was able to watch him closely when he was an assistant with us and what I saw was a bright, creative young coach who I thought would make an excellent head coach here,” Garrett said in a statement issued upon the hire.

You liked him when he was at USC, cool. But have you followed his career since then? Don’t answer that.

In giving Kiffin much-needed support, the Trojans are also bringing in Kiffin’s legendary father, defensive guru Monte Kiffin, while bringing back former Trojans assistant Ed Orgeron and possibly even stealing Norm Chow back from UCLA.

But even this is weird.

Chow left the Trojans after the 2004 season partly because Carroll was giving some of his responsibilities to the kid Kiffin. They can work together after that?

Orgeron is the real deal, a main cog in the rebuilding of the Trojans culture. But his tough-guy ways worked best in contrast to Carroll’s nurturing ways. Will he resonate as much when backed by a head coach who has not yet been around long enough to nurture?

The Trojans needed to replace Carroll quickly, but did they need to move so quickly that they compromised their future?

Word is, they were turned down by Mike Riley, Jack Del Rio and Jeff Fisher. Couldn’t Garrett haven’t taken a few more days and made a few more calls?

Much as he did with Carroll, Garrett is risking his USC career on this hire.

But this is different. The program now commands national respect with the expectations that demand a national presence.

At first glance, Lane Kiffin has neither.

bill.plaschke@latimes.com

twitter.com/billplaschke