It shows two things I reckon,
1/ The saying about the old Captain who noticed the engine failure and slid his seat back and started cleaning his glasses still holds water. The time pressure is often ‘perceived’ not real.
2/ Fuel imbalances in the 737 can be confusing. In the classroom they seem straight forward and then when the sim rolls around they are always more challenging than expected. I imagine in real life it is even more so.