redshift/black holes

http://www.edexcel.com/migrationdocuments/QP%20GCE%20Curriculum%202000/June%202011%20-%20QP/6PH05_01_que_20110627.pdf

it's question 18b)ii

the markscheme: The rotational motion (of the black holes) is small compared with that due to the overall recession (1)
(So) both black holes are still moving away OR (hence) the overall
effect when the black hole is approaching is to cause a small
reduction in the observed red (rather than a blue) shift (1)


i don't really get what that means... :c could someone explain?please
thankyou

Imagine I were waving a flag above my head in a circle. (You're standing still.) If I were standing still, you'd see the flag moving alternately towards and away from you.
Now let's say I start running away from you, still waving the flag. Now you only ever see the flag moving away from you, because I'm running much faster than the flag is moving backwards due to its rotation. The rotational motion of the flag is small compared with the speed at which the flag is recessing [that is, the speed at which I am moving away].