On the 200 lb. issue, I found another reference that said the original Kwan dao was only 90 lbs. and that was extremely heavy. On the 40 lb. issue, I think it's entirely possible that this weapon could weigh that much and still be used for it's original intended purpose.
Seriously- check out the guys at the armories and antique arms dealers- you probably won't even find a heavy lance weighing more than 20 pounds, and that was designed to be toted by a man on a horse. Anything heavier would require a counterweight on the other side of the horse to prevent saddle slide.
Also, at 90lbs, It also would exceed the total weight carried by any armed & armored archaic warrior.
Simple experiment- I bowl with a pair of 16lb balls (insert old joke here
