Another thing you can try is editing the mapping file that define how syncing to TFS is performed. Check out section 9.1.2 of the documentation for detailed information about the mapping files.
Adding the following line to the appropriate file should sync the assigned to field between Stories and work items:
One thing to watch out for is that the name of the assigned to user in TeamPulse must match a valid user name in the TFS project that you are syncing to, otherwise there will be a validation error when trying to sync.
the Telerik team
Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items.