You STILL got no answer.
Have you ever noticed that my timeline is different from yours ?
Should I stay up for the whole night to wait for answers ?
Sorry that I first had to built/correct a basis to discuss this myth, because Mr.NashbarShorts wasn´t able to do it.
If you want to bash, then do it with style, please. Mr.NashbarShorts didn´t seem to able to discuss on correct facts, or his memory was totally wrong.
Its obvious too, that he is a bad loser and hurt right now.

No clarification and still wrong numbers right now.
My thoughts about this myth ?
6 kg is a big number, but within, let´s say 8-9 hours, why not ?
Perhaps some mistakes, too ? No one is free of that.
Why should Carmichel invent sucha story or double the kg ? There is no logical reason for that.
I think he tried to refill over the day as much as possible, but his body couldn´t hold the fluid, or lost more than he could refill. I don´t think Armstrong is that stupid and drank NOTHING for the whole day and the article doesn´t say that anywhere. There is not written that he drank nothing and it seems logical for me that someone who loses fluid, tries to regain that !?! Chris should have mentioned that for some people I think.
Perhaps Lance had some kind of diarrhea and stomach problems, too or just earlier in the race. No rarity in such a heat-period.
But lets see what Carmichael said later in 2009 (but I still can´t find the "original" from 2003):
To understand the potential impact of today’s weather, remember back to 2003. There was a heat wave in France that year that killed more than 10,000 people. During the Tour de France, riders were beside themselves trying to get enough fluids, and near the end of the second week, Lance Armstrong started having a dehydration crisis. No matter how much fluid he consumed, he kept losing weight. His body wasn’t processing the fluids properly anymore and he was growing more and more dehydrated with each passing day. The Stage 12 individual time trial turned into a disaster. Between the morning and the end of the stage Lance lost something like 6 kilograms of water weight, and he lost 1:36 to German rival Jan Ullrich as well. Lance retained the yellow jersey, but only by 43 seconds. The following day, Ullrich should have been able to take advantage of Lance’s weakened state and taken the yellow jersey. He distanced himself from Armstrong in the final two kilometers of a summit finish and with a time bonus brought the gap to the yellow jersey down to 15 seconds. But by the time the race reached Stage 15, the weather had broken and the temperatures had cooled. Despite a crash on the final climb, Lance reached the finish atop Luz Ardiden first and extended his lead back to 45 seconds. By the end of the 2003 Tour, Lance would win by 1:06 over Ullrich.
The heat in 2003 put Lance in a dehydration crisis, and a change in the weather helped him get back on terms with his fluid intake....
http://www.trainright.com/articles.asp?uid=4485