The tl:task tag supplies information about a single task while the tl:taskList tag does the final output. The tag handler for tl:taskList is TaskListTag. The tag handler for tl:task is TaskTag. Both tag handlers extend BodyTagSupport.
Which allows the tl:taskList tag to get the task names from its nested tl:task children?()
A.A
B.B
C.C
D.D
E.E