Secondary motion can enhance or detract from the main motion. Think of the sails of Popeye's boat and the clouds behind them. The background has become a character. They move in rhythm to Popeye's body and the boat's motion, and when he leaves the wheel, the rhythm changes. And it's subtle enough that you're not likely to notice it at first. Name other places where secondary motion helps the scene.

Arcs make design and motion more interesting than straight lines. The motion is arced even when Pappy powers up into the air to save Popeye. What places in the animation do they arc the motion to make it more interesting?

Anticipation and follow through help carry the motion. On his boat, to speed up, Popeye takes a BIG breath in anticipation, he blows the boat onto shore and in follow through the boat goes aft-high when it lands. Are there other places where this principle is used?

Exaggeration. Popeye blowing the boat along is clearly exaggeration, but we accept it. Are there other places where exaggeration helps the story?

Notice how few metaphors are used. There are no eye-lines, no text balloons. The fight scene with the goons where it becomes a cloud of arms and fists, seems to be one of the last metaphors. Do metaphors like this still have a place in animation, why or why not?