Sthlm, 2015: Antigravity
In 2013 I started a project shooting in the Stockholm amusement park Gröna lund. I went on all summer and it really fed me up. So what do you do with project that go cold before finished? Put it in the freezer and let it rest. (This is NOT how I manage projects at work though)!
Yesterday I went there again and it felt quite nice to shoot that place again. I think the project is up and running again. Yay.
Sthlm street by Jimmy Dovholt 
Love this image and agree with you about putting projects on hold. A good project will go on for years, and inevitably during that period there will be times when you are fed up with it and lack any motivation. As you say ‘freeze’ it and come back to it later when the enthusiasm has returned. Otherwise your work will not be as good as it can be.
Yeah, dealing with Street Photography it is not very realistic to think you can do go out and shoot on a predetermined number of occations and get enough good shots to finish a project. At least that is my experience. On the other hand – will I ever finish my projects If I never set any deadlines? ;)
(Sorry for this embarrassing late response, Dave. I must have missed the notification some how).