I don't know. I don't know if I'd call him the Mel Blanc of Muppets.... I'd call him the Paul Frees of Muppets (Blanc and Frees are my 2 favorite voice actors of all time, BTW). Here's my reasoning. Blanc did absloutely everyone's voices in the Looney Tune Cartoons. Absolutely everyone. Where as Frees was part of a voice acting quartet in Rocky and Bullwinkle (counting the Narrator). Now Frees only had one main character in R and B, but he played absolutely everyone in the background. I think Jerry is the same.
Jerry only has a couple big Characters on the Muppet show, much more in Sesame Street, and his only true starring role was Gobo in Fraggle rock. But as for background characters.... It's hard to spot one that isn't Jerry. And that's better than being held back by a few major characters. You can really stretch your legs and play as many parts as possible when you do backgrounds.
Jerry only has a couple big Characters on the Muppet show, much more in Sesame Street, and his only true starring role was Gobo in Fraggle rock. But as for background characters.... It's hard to spot one that isn't Jerry. And that's better than being held back by a few major characters. You can really stretch your legs and play as many parts as possible when you do backgrounds.