No thinking necessary. Which brings me to my next, and possibly most important, point. Not only is thinking completely unessential to falling in love, it often ends up being an impediment. I thought so. It simply can't be done.
All relationships require work, no matter how good or bad.
If you mesh well, the work goes into learning about each other and developing those upper-layer connections mentioned above. If you don't, you have to spend your energy in forcing yourself to like or be attracted to the other person. At some point, one or both of you is going to get tired and need a rest. The difference is that, once you are rested, if you had solid bonds before the holiday, your lover will still be waiting for you after. If you've been forcing yourself to be in love, imagining characteristics where none exist, then it is all too likely that absence will not make the heart grow fonder, and one or both of you will realize what a sham you are living.