In watching the first part of the video, I cannot help but be impressed with how the Muppet industry "started small". They did not begin with big, multi-million dollar productions. Yet, from "a way to make extra money in college", it grew into one of the biggest entertainment companies in history.
The way they work the "human-arm" puppets has never ceased to amaze me. The amount of coordination needed for each hand to be operated by a different person boggles my mind.
One formula for their success: skilled puppeteers+skilled puppet makers.
Stay tuned for the other installments. There is a lot of puppeterring gold to be mined from these videos.