What do you mean "dump"?
If you're already loggin into websites via cookies, bitlocker wont do anything. They have free-range to navigate into your file folders, photos, and everything else. BitLocker isnt what protects the data; the lockscreen password/passphrase protect the data by obviously denying service. I still dont see the relevantcy of bitlocker.
These super-sophisticated ultra-hackers wouldnt be interested in the data i posses, anyway. I know whatever I say won't dissuade someone hell-bent on sticking up for BitLocker, but the argument makes sense against BL.
Lets do a role-play scenario here. Lets say I leave my Sp3 at a Starbucks. You find it, and 'steal' it. What happens next? BitLocker fairy comes and gives you a good wollopin'?