more cut an pasting from the official website:
Narrow handlebars for two of the escapees
Of the 14 in the lead of stage 18, there are two who are using handlebars that are signifcantly narrower than has been common for road racers in recent years. Adam Hansen (LTB) enjoys experimenting with equipment and he's been riding with 34cm wide bars for a couple of years now. (The standard is more like 40 or 42cm.)
You can see the difference in style that these narrow bars put him in.
David Millar's are also narrow but perhaps not as extreme as what Hansen's are.
What's the theory there - more of a TT style tuck?