As it happens, the answers for currently released Ghost are yes, yes, and yes, because the code isn't really aware of how to treat different kinds of disks in any case to be able to do things differently. In particular the released code in Ghost and the Ghost Boot Wizard writes only disk-at-once, requiring the disk to be in an unformatted state, and is completely unaware of the different options available for DVD-RW and DVD+RW disks (to say nothing of Blu-Ray) such as the 16k-block rewritable format mode in DVD-RW.

The unreleased complete rewrite I did of the optical disk support in Ghost and the Ghost Boot Wizard for GSS 3.0 did support the main rewritable disk formats to be able to write disks without requiring them to be blanked (as in the present code), but now that we're getting close to three years since the product was killed off that's unlikely to ever be shipped.