Yes, I have noticed that also, when I got to tickle my wife, I countdown from 3 to 0 and tap her foot each time. Definitely effectivePsychological teasing was a big thing for me too. It makes tickling much more effective I've found. Things like doing a countdown before you tickle or saying you'll tickle a spot but going for a completely different spot. It builds the anticipation and tickle fear just making it more fun as a whole.