This episode is a pivotal turning point for Eric Foreman. Throughout the series, Foreman struggles with the fear that he is becoming exactly like House: cold, clinical, and arrogant.
In this episode, he does act like House. He makes a gut call, ignores the simpler path, and it results in a patient's death.
This episode, "House Training," is widely considered one of the series' most gut-wrenching hours because it forces House—and the audience—to confront the one thing he hates more than death: a mistake he cannot blame on anyone else. 1. The Hubris of the Diagnostic Process
House is "training" his fellows (specifically Foreman) to think like him.