I think two weeks is good. I think everytime we visit this forum and everytime we log in and engage with this community, we disengage from our PMO behaviour. It gives up a chance to switch our focus away from harmful habits to contructive ones. Personally I think people should visit this forum as much as possible. In the moments when the urges are strong and even when we are feeling good, it helps us to stay focussed on achieving our goal.