combine node firmware upgrade with a OneFS upgrade

Ref page 25 of https://dl.dell.com/content/manual81478978-powerscale-onefs-upgrade-planning-and-process-guide.pdf :

In OneFS 9.2.0.0 and later, you can include the firmware upgrade with your OneFS upgrade. To perform a parallel upgrade that includes a firmware upgrade, run the following command where <install-image-path> is the file path of the upgrade install image and <firmware-path> is the file path of the firmware package.
isi upgrade cluster start --parallel <install-image-path> --fw-pkg <firmware-path>

Has anyone done this? Any feedback on it?

Is it recommended to do it this way, rather than doing the two upgrades separately?

Does it do the node firmware first followed the oneFS upgrade or the other way around?

Does it involve two reboots per node? (1 for node fw, 1 for onefs)