One Big Fluke

Another one I see a lot:

"Every statement is if/panic"

if _, err = dataFile.Seek(0, 0); err != nil {
  panic(err)
}
if err = dataFile.Truncate(0); err != nil {
  panic(err)
}
if err = json.NewEncoder(dataFile).Encode(teachMap); err != nil {
  panic(err)
}