Here are notes from Tissa David's lecture of 12/7/89.
Page one discusses rotoscoping.
Most of the lecture is on weight (and on page one it's relation to rotoscoping) and timing.
Every 5 rotoscope drawings
Trace movement action
Live action constantly moving so you can not have poses.
Click images to enlarge.
6 frames is hesitation. 8 frames - 12 frames (hold).
Don't add extra unnecessary actions that have nothing to do with your purpose of telling your story. Subtleties and sensitivities that add to your purpose are fine.
Anything for 2 frames is invisible unless you hold it for 6 frames.
Everything you do must be believable.