Perhaps you know more about the subject than Col. Bracknell.
Apparently, that rule is not set in stone and they have and do criticized presidents in and out of uniform. Perhaps Col. Bracknell should rethink his position or you have misinterpreted it.
Their ability to criticize the CIC is at the CIC’s discretion. Any time the officer gets too much notice the CIC can pull the plug. The way Obama handles McChrystal will signal how much hes willing to take from retired flag officers. If he bitch-slaps the General dont expect others to step up and go after him
Their ability to retain their retirement benefits and criticize the CIC is limited to what the CIC is willing to allow.