In reply to Removed User:
I did it in 3 days after flying out from Scotland 2 years ago. Went up to Abri-Simond bivvy hut the first night then did Tacul and headed back down to the valley. The following day I headed up to the Abri Simond again then did an overnight ascent and arrived ontop about 6:30 in the morning via the 3 Monts route then descended the Gouter.
I think going to 4000M first on Tacul really helped. I'd have struggled to go straight up completely unnacclimatised. Even with this I felt pretty gubbed on the last few hundred Metres on Mt Blanc and was keen to get off the summit quickly and lose some Altitude. One of my best experiences in the hills.
However, I would definately not recommend it to everyone. Acclimatisation is such an individual thing-I'm sure you have a fair idea how you get on normally-those last few hundred metres do make a difference though, I certainly felt them!
The three Monts route was great by the way and very quiet, cant recommend it enough. Coming down the Gouter was a bit of a circus. I was really surprised to see some clients in total rag literally being dragged up the hill by their guides on the bosses ridge. They didnt look well acclimatised-I'm sure this isnt representative of most guide/client relationships but I reckon there is pressure to get people up in short acclimatisation plans, particularly on Mt Blanc.
hope that helps
Jon