Virtual Systems Analysis - S3-E16
Continuity mistake: When Annie is talking to Abed in the study room, next to Troy and Britta, the Dean's "Puttin' On The Ritz" cane is leaning against some books, towards the right. When the Dean comes back in to claim it, it is leaning towards the left.
Answer: It was part of the plot that when the boiled yam was dropped it looked like it was stepped on (which it never was). So there was no way to tell the difference between the flesh being soft because it was boiled or because it was stepped on (in the show that is, I don't know if one could tell the difference in real life). Plus, the rest of the yam wasn't boiled, so there was no evidence the yam was sitting in boiling water.
Bishop73