I used to weigh just once a week but found myself cheating for a day or two after weigh in figuring I had about a week to get it off. What works best for me is weighing in twice a week. It keeps me accountable and I see more of a difference in the scale than you do weighing in daily. Whatever works for you is what is best. Having said that, I really don't think weighing in a couple of times a day is good as your weight will change throughout the day. See if you can at least cut down to once a day at the same time everyday.
I used to try to follow the conventional wisdom to weigh once a week. But I always "cheated" and checked a few times during the week and felt guilty about that, like I was doing something wrong. One thing that has been great for me about 3fc was seeing lots of VERY successful losers and maintainers who were daily weighers, which allowed me to give myself permission to weigh daily. I even started a thread this month to track daily weight, which is something I've NEVER done before, and couldn't even imagine doing.
So I absolutely do not thing it's wrong to weigh daily. BUT the issue is whether it works for you personally, to keep you motivated and on plan. If you get upset by seeing NORMAL fluctuations, and maybe even find yourself thinking it's not worth the effort to stay on plan, then definitely stop weighing so frequently. But if that's not the case, and if tracking weight daily helps you want to work to meet your goals, then I don't think there is anything wrong with that.
I'm a daily weigher also, it keeps me accountable through out the day...sometimes I weigh myself when I get home from work too...just to see what my daily weight fluctuation is. It's a little neurotic...but it works for me. Just do what works for you.
I'm good with daily weighing, but it took a long time for me to be okay with me accepting the reality of weight fluctuations. I no longer get depressed seeing the scale jump up 2 or 3 pounds.