As a UK driver, I was taught to shift to neutral and apply the parking brake when stopped for long enough to do so. The reasoning given by my driving instructo

As a UK driver, I was taught to shift to neutral and apply the parking brake when stopped for long enough to do so. The reasoning given by my driving instructor was that this secures the vehicle and makes things just a little more safe for everyone. If I am stopped in traffic with my parking brake on and sometime lightly rear-ends me, my vehicle may not move at all. If my parking brake were not applied, the probability of my vehicle not moving at all drops significantly. If I am rear-ended without the parking brake applied such that my vehicle rear-ends someone in-front of me, I am partially responsible for the damage caused ahead due to my failure to secure my vehicle. This is only tangentially related to taking my foot of the clutch. I depress the clutch in order to apply the parking brake correctly. Once the parking brake is applied, I simply have no need to continue to depress the clutch. It takes me very little time to apply the parking brake and then release it and so I tend to do so when stopping for more than a second or two.