"The bless tool was unable to set the current boot disk" error in bootcamp macOS Sierra
I was able to resolve macOS Sierra error about the bless tool by using the pictured setting on WinClone 6.0.3. I did not restore from winclone backup but rather just made my BCP bootable as an EFI instead of legacy BIOS drive. For some reason macOS started to view BCP as an unbootable legacy BIOS drive. My guess is installing Paragon suite of tools like NTFS, Hard Disk Manager, and ExtFS for Mac had this sudden and unintended result during the runtime environment. 



To prevent BSOD sysprep appears to be necessary when restoring WinClone backups on external drives.