It's little details like these that make a good video great. I have yet to see a fully detailed video, by the way. (Maybe one day I'll write a story...)
It's like, why are some movies okay, and others great? Because of all the little nuances that add to it. The thoughts behind the tickling sometimes are almost as good as the tickling itself. That's why many people like plots, even if they involve no words. Like, someone works late and is tickled at work. You see her dangling her heel, knowing what will happen soon. But if she has a nice outfit on, the video is better. And maybe a pen that has a feather on the end in her assortment of pens. How she carries herself - sexy, innocent, whimsical... Does she have a bounce in her step, a very professional walk, a slight skip, like she is a playful person? All these things are great and involve no words.
You could shoot the shoes on the desk, and slowly pull back to reveal the bottom of her feet being stroked by her own feather pen, while the shoes are in the foreground. Then slowly turn the camera so that you can see the shoes in the foreground, her feet being tickled, and her face laughing silly.
Maybe one day that will be in a video....