Rotating each joint manually is indeed a bothersome process..

In Forward kinematics you control the hips and leg joint and knee joint and ankle joint to get a foot where you want it.
In Inverse kinematics you can grab a foot and put it/key it where you want it...

This last bit is just something you might want to experiment with...- I should not criticise but Chad Browns layered approach in that video does not (to me) achieve main keyframes with a dynamic pose / effective line of action.

The way I like to animate something like this, is to Key the full pose in the 'Up Pose' the 'Passing Pose' and the frames where the model contacts/strikes the ground, and again when the model leaves the ground.. I like to (was told to) make the poses in these frames really 'pop'. Without this models seem a little ragdoll-y.