I know I'm late coming in on this one but...
The doctor got defensive because he was rather bluntly told that his method was wrong. I would also be defensive!
There is more than one way to pluck a chicken, so to speak.
The best artists can start anywhere on a figure and end up with great results.
Remember different does not equal wrong, necessarily.
And for what it's worth (you can judge for yourselves, I know), I also always begin with the eyes!
Let's not be so pedantic! This is art, after all.
"What if imagination and art are not, as many of us might think, the frosting on life, but the fountainhead of human experience?" - Rollo May from The Courage to Create