Kind of, but not entirely. You target a player and get position. Just like if you are in a zone vs man to man... It is how you are taught & coached.
The Murray twins were great at blocking out. The team defense was not good... I guarantee you that Kenyon had blocking out locked in to their muscle memory at the age of 5.
Yes, blocking out still occurs with bad defense.
But, AS A TEAM, a HIGH LEVEL of blocking out can't occur with defense AS BAD as it was during Fran's years at Iowa. It doesn't matter if just a couple guys block out. Everyone has to.
A defense in rotation puts guys in even worse rebounding position than a zone does. Guys get shoved under the hoop. Guys lose their rebounding angles. Assignments get distorted. Under Fran, Iowa often wasn't sure who to guard once they were in rotation. Same as for block out accountability. Basically every step that an offense is able to break down a defense, ends up in one way or another, amounting to a step lost in rebounding positioning.
Like the Murray's, basically every college player has long been in the habit of boxing out. That pretty much makes my point, that once a defense has been broken down, the angles to execute effective blockouts have already been lost. It's not a habit thing. It's the result of bad defense.
For full disclosure, it should also be mentioned, that for certain situations, Fran taught a rebounding technique that emphasized pursuing the ball, rather than blocking out at all. It seemed to only further confuse his players. And it's not a technique that I feel should ever be employed by the smaller/less athletic team.
But in general, the worse a defense is, the harder it becomes to block out. Name one team that ranks toward the bottom in defense but still blocks out at a high level. I'm not sure I've ever seen one
