I agree that 5kg per week is a lot to aim for.
It can be very confusing and stressful starting out - I know it was for me when I first started changing what I was eating, especially when my weight started going ballistic, losing 4kg on week then putting on 8
I too didn't know whether to eat less, eat more, give up, exercise more, yadda yadda.
Basically I just kept dong what I was doing and everything evened itself out. If you just do what seems sensible to you I'm sure you will find something that works for you.
35kg lost. (November 2005 - October 2006)
15kg gained again (as at October 2010).
Back to the drawing board - Let's do this thing!
"You can't change the winds, but you can change the sails"
"Reach out and take control of what lands in your lap"