In Performing a study for example, with a secondary service at 480 volts and a 2500 KVA utility owned transformer, if you include the utility fuse on the primary of the transformer it could reduce the line side energy at the customer incoming PD.
On the other hand, you have no control of the utility fuse which can change at any time without notice to the customer, so this would mean do not include the utility fuse.
Thoughts, comments... thanks Jimmy