Graphical displays for monitoring medical patients

I attended your course this very day and was astonished. You are the clearest, finest, and most logical–thus most perfect–teacher that I have ever seen–and I have had many, many classes with very, very excellent teachers.
I do not cavil, I am not captious; but I note that on page 111 of Visual Explanations that the value printed in red for “Reg Insulin”, which I interpret to signify the most recent value injected that day, is in error. It should read “0” if insulin therapy was discontinued.

3 units of insulin administered to a euglycemic patient would cause certain, horrific & a sadly theatrical death.

What gives?

Mike