Thanks for the clarification Erik! Huge help!
Still a little confused, however.
As you said, Line 13 specifies CHW and then on line 65 we change it to HWC. That's fine. However, it says in the openvino docs that the mobilenet-ssd model used by the hello_world.py example requires CHW:
Image, name - prob, shape - 1,3,300,300, format is B,C,H,W where:
B - batch size
C - channel
H - height
W - width
Channel order is BGR