.. then you don't have time to catch the 4th row, it'd wind up instantly, to see it you'd have to scroll up again. So this is why "double take" here. But it would only work the first time, on the 5th row, and as you scroll down to 6th, 7th.., there is no need of double take". This scrolling events logics are hard to implement, because every time you change scroll direction, you'd need to reset the counts.