Thanks for posting! I saw that special awhile ago, and it's great to see that clip again. I love the part where Marty tries to say "Hi" to Bert as he leaves and says, "He never talks to me!" LOL
It's so strange seeing newer performers taking up the torch of classic characters like Ernie and Bert, and then showing a clip of Jim and Frank performing them years earlier. Definitely creates a special sense of history and legacy. If that made any sense, hehe.
Also loved seeing Frank perform Grover (one of my personal favorite characters and sketches of his). And he's very right, people don't understand or appreciate how difficult it is to create and develop these characters. Instead of saying they just "do the voice" of a character, the better term would really be "he/she performs the character."