False. Those are not the only answers. There is another answer that states what he said could be true.
What exactly causes the bug to happen seems to be a bit of "lag" in the server calculating fall damage (the server does it to prevent players from hacking fall damage prevention.) and when the server lags that information, it can send it twice, three times...as many times as the lag lets it. It's entirely possible for it to be lagging enough to make you die from full health. All I was doing was sprinting on the ground when deathmatch started (on purpose, I like to be moving as soon as it starts.) and I took 8 hearts fall damage. Next game I did the same thing and took none. The only different might have been the platform at the corn that I started on, which still proves the point that there is a issue with taking tons of fall damage for no reason. Yes, I was at full health when I teleported to deathmatch both times, I always check to make sure before deathmatch. And yes, I wasn't lagging long enough for somebody to be hitting me with a sword, I was the first one there in fact and got free hits on the only other guy for his lag.
I once even logged onto a server one day, and died of fall damage in the lobby. Upon testing further, I realized that fall damage is disabled in the lobby. That's got to be some server mess up there, because about 5 other people also died and when you log into lobby, there should be a platform directly beneath you. That's not to mention dying of fall damage when the game goes to pre-game and you are about to rush corn. Damage is disabled there too, I've been next to a aimbot hacker who was trying to hit me, so obviously he was close enough to punch me. You can't tell me there is no issues with fall damage killing you instantly from full health upon teleportation, even Chad has acknowledged it it.
You are right about one thing though, it's not MCSG's fault. A temp fix is trying to be made until Bukkit/Minecraft fix it themselves.