I normally vary it on a weekly basis - some weeks, I don't use any weekly or activity points, followed by a week where I'll have one big meal dipping into my weekly points, followed by a week where I dip into them on a daily basis. No rhyme or reason, it just depends how I feel that day/week!
My experience, though, has consistently been that I lose more weight the weeks I do not use them. Some people are at a point where adding more food into their diets boosts their weight loss, but I've done a lot of experimenting over the last year and that is my experience.
For example, 3 weeks ago I was spot-on -- no weekly or activity points used. I exercised every day and earned 50 activity points and I lost 3.9 pounds.
The following week I had a bad week - I exercised every day, earned 49 activity points but I ate ALL my weekly and ALL my activity points. I think I was at -1 and I gained .4 pounds.
Last week, I earned 49 activity points but didn't use any of them - I used all my weekly points and I lost 2.2 pounds.
That's how it has been all along for me.
The harder you work, the harder it is to surrender.
~ Vincent T. Lombardi ~