The recommendation is mostly coming form TREK.
http://velonews.competitor.com/2010/...r-tubes_121389
The theory is that the stem directly on the top of the headset causes a stress point.
Whether there is anything to it, it seems to me that a 5mm spacer under the stem is cheap insurance.
It would also appear that Saxo Bank's mechanics think that there is something to it. Otherwise they wouldn't have set up Cancellera's bike like that.
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
Last edited by merlinextraligh; 09-15-10 at 10:13 AM.