For me, it's all about the preps. When I was on a 4/4, it was limited to 3 preps, and my classes were all 40 or less. You got overload pay if you did more than 3 preps. The problem was--I was always prepping NEW classes, so I rarely got to repeat stuff. Partly this was my fault, and partly it was due to being the only representative of my discipline.
On the other hand, if I was teaching one prep, but it was 2-3 sections of freshman comp, lord have mercy. I always felt sorry for my friends in English. My field requires extensive prep because of all the visual materials, but the grading in composition is never-ending.
I know that a lot of wise old owls who guided me when I started my career said that it really wasn't about the number of classes so much as the total number of students and the nature of the classes.
I started my career at a school like that - 4/4, 4 preps per term, and they always asked me at the last minute to pick up an extra class or two because an adjunct quit, or they planned for only one section, but had last-minute enrollments, or some other lame-a$$ cr@p. I tried to refuse the extra teaching assignments on the grounds that my contract was a 4/4, but word got back to me that they "really need me to be a team player". It was me, and three adjuncts, all of whom were teaching two or three classes per term. When I told them they really need to hire two more full-time faculty, the response was, "We really can't justify even one more full-time faculty in your area". I started sending my resume out that week. Somehow I managed to get something published while I was there, so at least I was able to move.
