In regards to the comments about the time it spends to work up from right-handing...
I mentioned upthread about how i've generally thought of there being four "tier levels" of Muppeteers (for a number of years, i thought of this as three tiers but over the last couple, i've adjusted this to four) based on how much work they do with the Muppets and not necessarily talent level. They're not even really based on "experience" as much either other than obviously those just starting out would start out on the fourth tier. When i talked about this, i mentioned that a lot of us are a bit concerned since we saw a first tier Muppeteer being subbed by a fourth tier one.
Now as this pertains to Richard's hazings of newer Muppeteers who were anxious to move up, for one thing, as great as the guy was in many ways, he could be a bit overly vicious at times (whether it be with newbies or Jim himself) - but at least he was also aware of that character trait of his and could balance that out with his generosity - he'd put someone through the wringer and then buy them dinner.
His lectures about how he had to wait eight years before he had a major character while having a good message about how the process does indeed take years...it was also just very exaggerated. For one thing, he fudged big time on how long it took him (it took him six years before he played Scooter and that's even giving him the benefit of the doubt that that was when he reached the level of being able to perform a major character since it was obvious from the two Muppet Show pilots beforehand that he was a valued enough member of the team to be doing signifcant roles. Even though the character itself didn't become a star, four years prior to Scooter, he was cast as Mildred in Valentine Show and if one just looks as that production as its own entity - a pilot that hopefully would be picked up as a regular series, he was playing someone with a good amount of screen time/lines and whose role seemed to be the group's den mother - someone who kept a fair amount of order and kept others under control. She was the main one to chat with the guest star when she arrived. He had lines as early as his 1970 debut in the Great Santa Claus Switch, he was just as much a part of the ensemble by 1972 when they did the Wild String Quartet sketch on Ed Sullivan and was starting to get a number of supporting roles in Sesame sketches within that year. So while the message he would try to convey to the newer Muppeteers had merit as a lesson, he couldn't really use himself as the best example to illustrate this point - and he had to do a lot of exaggerating to sell it.
...Plus things have greatly changed over the last few decades. In Richard's day, not a lot of people thought about being a television puppeteer/Muppeteer as a full time career. Someone like Richard could telephone up Henson, be told that auditions were that day and he could essentially walk in off the street without much experience and not only be considered but also cast. These days, people grow up thinking it may be a career path they may want to take. They have the chance to work with local troups/stations and other puppetry teams before they do they audition for Henson (as was the case with Steve and Kevin). Due to the advent of camcorders, someone can train themselves at an early age how to work in front of a camera (and do so while viewing a monitor). One could also attend workshops, classes, even colleg training. A puppeteer just starting to work with Henson can come in with a lot of skills already well developed. Of course, once they do get in the door, they also have access to what is by now a very well-honed in-house training program that further hones the skills they're coming in with. Now this doesn't imply that one shouldn't work their way up starting on that fourth tier and working their way up a tier at a time (it is possible to maybe skip a tier but shouldn't really be more than one), but the time it takes to advance can be quite quick compared to how long it used to take.
Still that first tier is a very special one. Artie is obviously very good and will be a huge asset to the Muppet team. But to take on a task like this one was too big a jump too soon - for anyone to expect him to give a Steve-level performance regardless of raw talent or skillset he's shown behind the scenes was unrealistic. It's a bit like turning over CEO duties of a major company to someone who just joined it less than a year ago even though they may have demonstrated super leadership ability in their local branch. He may be one of the Muppets' most valued performers within the next five to ten years, but to take over for Kermit at this point was just too ambitious an undertaking. And i think all of us will have an unresolved sense of restlessness until we find out what happened with Steve and who will be performing Kermit the next time we see him.