“Planners are a funny lot. They carry neither sword nor pistol…”

A rhyme about planners has been cited in print since at least 1959:
 
Planners are a curious lot,
They wear not sword nor pistol.
They walk stooped over—never trot,
Because their balls are crystal.
 
The rhyme has been popular both in business and in the U.S. military.
 
     
Google Books
Proceedings of the Thermoelectric Symposium, Whirlpool Corporation, Shoreham Hotel, Washington, D. C., October 21, 1959
St. Joseph, MI: Whirlpool Corporation
1959
Pg. 105:
I repeat a cute little jingle relative to this:
 
Planners are a curious lot,
They wear not sword nor pistol.
They walk stooped over—never trot,
Because their balls are crystal.
 
Google Books
Conference Proceedings of the Eighth International Forum for Air Cargo
Society of Automotive Engineers
Volumes 8-10
1980
Pg. 113:
“Bemoan the planner’s unhappy lot,
Unloaded is his pistol
He cannot fructify his plot
Because his balls are crystal.”
   
Google Books
Body of Secrets:
Anatomy of the Ultra-Secret National Security Agency
By James Bamford
New York, NY: Doubleday
2001
Pg. 73:
On his (Lyman Lemnitzer—ed.) Pentagon desk was a crystal ball and in a drawer was a favorite verse:
 
Planners are a funny lot
They carry neither sword nor pistol
They walk stooped over quite a lot
Because their balls are crystal.
   
Prof. Dr. Dennis Alexis Valin Dittrich
JokEc - Jokes about Economists and Economics
1st WWW-edition 24/10/1994 (d/m/y) Update 16/04/2001
(...)
Morry Adelman at MIT claims that he heard this at Shell long ago:
“A planner is a gentle man,
with neither sword nor pistol.
He walks along most daintily,
because his balls are crystal.”
Mike Lynch, MIT
 
Google Books
XVIII Airborne Corps in Desert Storm:
From Planning to Victory
By Charles Lane Toomey
Central Point, OR: Hellgate Press
2004
Pg. 175:
Planners are a unique breed…with neither gun nor pistol.
They always lag and never lead…because their balls are crystal.
from an XVIII Airborne Corps Plans Briefing, 1991
 
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‏@netoinloscabos
Planners are funny lot
They carry neither sword nor pistol
They walk stooped over quite lot
Because their balls are crystal
ChiefStaff #JFK
2:14 PM - 22 Nov 2013