Yes, in the Bare Metal Server there is an option, I think in the Boot Profile area, for “boot to disk if idle”.
DHCP Option 43 has, I believe, a slightly better option in that it can display a boot menu and include the local disk as an option (or set that as default option with a timeout).
Changing the systems’ BIOS options to boot the hard drive is still far preferable to either of these. If the Bare Metal Server is offline but is attempted by the client, the client can still get stuck on a “TFTP Failed” message at startup.
With the clients’ BIOS / UEFI set to boot the hard drive first, you’d need to manually interrupt the boot sequence with F12 in order to select a PXE boot. For reimaging existing clients, we have a task in the OS Deployment and Bare Metal Imaging site for “Force network boot” that performs a one-time reboot to PXE, so you can still reimage existing clients without having to visit them to hit the F12 prompt.