Thinking back on my college experience, I would mostly have to agree. The younger, less experienced teachers (probably teaching assistants or grad students still) were merely tolerable most of the time. I had some rather brilliant tenured professors and their expertise, particularly in the area of research and those minute details about their area of teaching was something that just wasn't found with the TA's. The teaching assistants were okay to run basic science lab classes and all, but when it came to my major studies, I absolutely learned the most from my professors. Getting beyond the basic classes and into my major fields of study was a great pleasure because I was no longer at the mercy of just "good enough to dispense the material" teachers and finally into the depths of my studies with professors who, by nature of their years of research, just had much more to offer than the basics.

I did have one regular teacher (not a professor) who I do feel did a really good job, but most were rather forgettable.

Now, I did have a few professors that were almost far too along the line of expertise to be good teachers though. For instance, I had a chemistry professor who was actually one of the scientists who worked on the Manhattan Project. The man was brilliant, and if I had actually been a chemistry major I probably would have been thrilled with his level of expertise, but he was a horrible teacher to undergrad students who weren't necessarily chemistry majors and were a bit lost in his lectures. So, there is a point at which the expertise can be negated by bad teaching.

Still, most of the tenured professors I studied under were very good teachers and I learned a great deal from them. I enjoyed the challenge (except in chemistry) and detail they could provide that just wasn't quite in the grasp of most of the younger teachers yet. I found their comfort with their subject matter helpful, and yes, most of them were pretty humorous because they had so many interesting stories to tell while they taught. Definitely kept the interest level up.