Why doesn't "--debug" switch produce debugging messages?

The "--debug" switch doesn't appear to cause any change in the output (see below). Is it expected that there should be additional debug messages for this command?

Here's a transcript showing that "--debug" switch does not appear to produce any additional debugging messages:

$ msp430-bsl --swap-reset-test --invert-reset --invert-test --speed=38400 -r -e -p /dev/tty.usbserial-FCV6I5XN blink.hex
Programming: OK
$ msp430-bsl --swap-reset-test --invert-reset --invert-test --speed=38400 -r -e -p /dev/tty.usbserial-FCV6I5XN --debug blink.hex
Programming: OK
$ msp430-bsl --swap-reset-test --invert-reset --invert-test --speed=38400 -r -e -p /dev/tty.usbserial-FCV6I5XN -v blink.hex
Debug is False
Verbosity level set to 2
Python version: 2.7.1 (r271:86832, Jun 16 2011, 16:59:05)
[GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)]
pySerial version: 2.6
action list:
   mass_erase()
   program_file()
   reset()
   reset()
Write segment at 0x4000 2490 bytes
Write segment at 0xffe0 32 bytes
Programming: OK
$ msp430-bsl --swap-reset-test --invert-reset --invert-test --speed=38400 -r -e -p /dev/tty.usbserial-FCV6I5XN -v --debug blink.hex
Debug is True
Verbosity level set to 2
Python version: 2.7.1 (r271:86832, Jun 16 2011, 16:59:05)
[GCC 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2335.15.00)]
pySerial version: 2.6
action list:
   mass_erase()
   program_file()
   reset()
   reset()
Write segment at 0x4000 2490 bytes
Write segment at 0xffe0 32 bytes
Programming: OK