I would go so far to say their Windows support is deliberately spartan and minimally baked, what with crippled ATA-133 disk speeds, having to hack the MBR for AHCI, disabling sleep as it bluescreened on wake otherwise. Thankfully I use a 17 inch MBP who's monster battery gives me over 4 hours of life, but a 15 you would be lucky to get 2 hours, dreadful. Work around the faults aside they run Windows fantastic and I wouldn't be surprised they wilfully don't optimise it to keep OSX ahead for the novice bootcamp user.
Have you tried throttlestop?
http://www.techinferno.com/downloads/
You have to register to get it now..