In reply to Tris: Having just completed the drive to / from chamonix i thought i would let you all know the route etc.
Gloucester -> Flkestone for the le shuttle was about 3 1/2 hours and ok.
Le Shuttle is pretty good, fast and was on time and pretty easy, though not cheap, £200 return!
We then did calais -> Rheims -> Troyes and stopped off over night in an aire near troyes, thinking we were half way. Unfortunately we parked up near a refrigerated van which kept us up most of the night. We set off from Gloucester at about 9.30 am and stopped driving near Troyes just before 8pm. I don't drive so my wife did all of it.
Next day was troyes -> Dijon -> Bourg en Bresse -> Geneva -> Chamonix. That was quite a long stretch after a bad nights sleep. Taking almost 7 hours as it rained heavy all day. We also spent about 45 minutes queueing for diesel, and then another 30 mins at a large peage just outside Geneva heading towards Chamonix.
There was heavy snow falling down to Les Houche when we arrived, and we faffed for an hour trying to find some fresh water for the van - we failed every where was frozen. We also had to put the chains on, but we made it to Argentiere and parked just in time to get a meal.
We were in a long wheel base, high top merc sprinter. The peage was about 110 euro's each way. Only a bit less than the cost of the diesel!
The drive on the way back took about the same length of time. I had been messing with the satnav a bit. It decided that the fastest route back was via Lyon! as it turned out it was faster roads but because we were in a big van it didn't help much.
Heading east from Macon the roads are not that fast. Quite mountainous, lots of tunnels (so no over taking) and in bad weather everything slows down.
We ended up usually cruising at about 110 Kph. We didnt really encounter any jams, but we headed out on the 22nd and back on the 29th.
I had assumed that getting down to Les Arcs or Tignes would take about 2 hours longer than Chamonix (from looking at google maps) but i don't think thats quite right. When we headed back we went just north of Chambery to Lyon, which doesnt seem much further to go to Tignes etc. So maybe just ab hour more. Though the road does seem quite small for quite a distance getting to tignes.
Cheers
Dave