The first thing one needs to experience when playing with the oblongs of Gift Four compared to cubes of Gift Three, is that oblongs are not as stable as a cube. A cube never falls over, but an oblong, when either standing or sitting has the potential to tip over.
So a child quickly learns about balance and off-balance. Off-balance creates movement, and movement can be directed. Both balance and movement, in order to be effective, require accurate placement. In writing up her report Joanne said, "Excuse me, but now we're talking about gymnastics!"
The making of dominos, as directed in the Kindergarten Guide (pg. 48, figs. 3-6), takes a steady hand and also teaches the properties of weight and balance. The unleashing of the potential energy as the oblongs fall in different configurations is what holds the child's attention, as they repeat the game over and over.
Bob preferred to play and build a tower using all the blocks from two sets of Gifts 3 & 4; taking advantage of his experienced surgeon hands.