With regard to the recent discussion on Planning and Conducting Experiments, Bob Hayden was right on target, as usual. The changes were intended as a clarification, not an expansion. These are concepts one should be familiar with when planning a study or critiquing someone else's plan.
These can be discussed without actually completing the inferential analysis of data from designed experiments. Often, a graphical display is good enough for a preliminary analysis. On the other hand, all of these concepts can be illustrated with two treatments, where the comparisons (paired or unpaired) can be made with inferential trechniques covered in the course.
We do not intend that you teach analysis of variance; we do intend that students appreciate the fact that study design is one of the very important aspects of statistical reasoning, some would say THE most important. It has been said that the randomized, comparative experiment is one of the most important contributions to science in the twentieth century. Should not students being introduced to the subject know this?