I am a big worrier too. I worry about small scale things and big scale things. Hell, I worry about worrying. I can see it would be difficult to set aside worry time for an hour and then not worry outside of that time. Maybe we do need to try hard at it. I will give this technique a good effort and let you know how I fare. Controlling the mind is no easy task and takes practice. You may just need a little more time and honing before you get it down pat. I am supposed to practice mindfulness, but my therapist told me it's a skill and won't happen overnight. I imagine the same is true for you. Cut yourself some slack, and just keep trying until you get better and better at it. I bet in time you will be a pro. Practice does make perfect after all. Good luck to you. All the best.