The problem with a restore from a Time Machine backup is where the information going to be restored - the SSD part or the HDD part of the Fusion Drive. Apple has said that the OS and all of the applications that come with the OS will be stored on the SSD portion. When you restore from a Time Machine backup made on a different Mac, the Migration Assistant should be Fusion Drive aware in order to place data being restored to the correct part of the Fusion Drive. So, I wonder if not only the Disk Utility, but also the Migration Assistant (and perhaps Time Machine) is/are also Fusion Drive aware. The normal migration path from an earlier Mac to a Mac with a Fusion Drive should be to use the Migration Assistant to bring over all applications, settings, and user data from the Time Machine backup made from another Mac to the Fusion-Drive Mac. Hopefully, Apple has thought of that and has a mechanism that restores from the Time Machine backups and places the data in the correct part of the Fusion Drive. Apple has not revealed yet how this is to be handled. The alternative to this is to install all applications on the new Fusion-Drive Mac manually (hopefully they would install on the SSD), and then use the Migration Assistant to bring over the settings and the user data from the Time Machine backup.
Another way this could be done is that the Migration Assistant (or the Time Machine backup) places everything to the HDD during the Time Machine restore, and then the brains behind the Fusion Drive gradually repositions the applications and the user data to the SSD portion of the Fusion Drive as applications are being used. This process may take weeks or even month to relocate the proper applications from HDD to SDD based on the algorithm that Apple has programmed into the Fusion Drive technology. Thats probably the reason why Apple pre-installs all standard applications that come with the Fusion-Drive Mac onto SSD at the factory.