While I am totally against military bullSh1t whilst on operations, a line in the sand must be drawn between being a professional military organization and a rag tag outfit, especially when in the eyes of our Allies.
The question is though - At what point do we draw the line?
To answer your question, may I commend to you:
"On the Psychology of Military Incompetence" by Norman Dixon
Pimlico 1976
Especially the articles relating to the Boer and Israeli forces, neither of which were noted for their dress standards, but both of which were particularly effective at giving others - including our good selves - a pretty good kicking.