Don't try to pull them apart - cut them, making sure each portion has an obvious eye or growth point. You can dust the cut surface with sulfur to prevent any disease issues if you like.

Thank you for your response. That sounds a little scary but when the time comes to plant I will be brave and cut them. :)

Don't be scared - cutting, either with shears or a sharp knife, is the accepted way of dividing dahlia tubers. Much safer for the tubers than trying to pull them apart!! And you can be assured of getting at least one eye for every division.

"If I accidentally knock the sprouts off will the tubers still be okay"

Yes, a couple new sprouts will grow in a couple weeks from around the base of the knocked off sprout. No worries.

Large clumps can be real bears to separate. Sounds like you have a good idea on how to go about it... do your best, and don't worry about saving every last possible tuber. All the tubers do is to supply food to the sprouts, and especially in the huge clumps, there are sometimes more tubers then sprouts to be nourished.

Thank you for your response also. :) I really do want to be successful and have some nice dahlias this summer.