This could save your life

[Bmblbzzz]

Turning right at a T junction requires crossing two streams of traffic at once. A left-right stagger means only one stream is crossed at a time, reducing waiting time at each stage of the manoeuvre, and thus cutting impatience, and more importantly allowing you to focus fully on one thing at a time. This one-thing-at-a-time principle is well known in (Yes) Dutch road layout for instance.

Ed: And above all in roundabouts.