One of the biggest challenges of the tek cave is the cave itself, particularly when trying to get all of your tames inside before the door closes. Oftentimes, even with the conga line method, things like rexes will get piled up against the wall instead of going through the door, which means you have to go outside from the cave to manually move them...at risk of going too far, causing the cave to unload, and send what tames you have inside plummeting through the floor.
If the tek cave remains loaded while the door is open, this problem is avoided.