Do I have to remind everyone of the origin of the term?
In 1961 Texas was 8-0 and ranked #1 in mid to late November when the 2-4-1 TCU Horned Frogs came to Austin and upended the Horns 6-0. After the game, DKR said, “They’re like a bunch of cockroaches. It’s not what they eat and tote off, it’s what they fall into and mess up that hurts.”
Hence a cockroach is a team with no aspirations that upsets a team with national championship aspirations.
I wouldn’t say that Texas Tech cockroached Texas in 2008 anymore than I would say that Texas cockroached Nebraska in 1999 because the upsetters were good teams.
I would say Texas cockroached OU in 2015. I would say Iowa State cockroached Oklahoma State in 2011. I would say Baylor cockroached Kansas State in 2012. I would say Oklahoma State cockroached OU in 2001. I would say Kansas St cockroached Texas in 2006.
Cockroaching happens all the time. Teams that never compete for conference titles but routinely upset teams who do are recidivist cockroaches.