well, all I can tell you is that I joined the army in 1987 and it was in use then. I do have a good story about the m67 though. During Operation Just Cause, we set up a perimeter at Rio Hato in Panama. Well, we went out and set up booby traps to the front of our position. We were using grenades cuz we ran outta claymores. So, we changed the fuses on the frag grenades with the smoke grenades because the smoke's fuses were instant no delay. well, the problem came when we moved out the next morning we went and policed up our booby traps. In hurry we put all of our frags together. That ment mixing the booby trap frags with the "normal" delayed fused frags. Not Good! we ended up going down on the beach and blowing up the whole batch with c4, then getting a reissue of frag grenades. Seems the army never has a shortage of grenades.
BTW: Iam glad you could see that it's a trainer, not saying that your a moron or anything but, I 've seen people who have been trained do stupid things before and the said part is they dont only kill themself but usually someone else too. Thats why people like me have to preach about it sometimes.