Most inbetweeners aren't this good. Then again most animation isn't either. I did 3 years of this classical animation at school and though I knew these techniques and could do this work (but take a little longer), I still wish I was half as good as this guy who makes it look effortless, but my goal back then was just to get the fundamentals down and then apply them to computer animation which was MUCH more rare in the early 90. Unfortunately not all the commercial work in the late 90s was character based so I became a more diverse jack of all trades. These days there's more character work, classical and/or CGI, but most don't have the quality animation like this guy's work since that requires time-talent-budget to accomplish, so it's ultimately not a much better situation for ambitious average or junior animators who want to do better quality character work.