Some clarifications in wiki/QemuXorriso

doc/qemu_xorriso.wiki

@@ -20,15 +20,13 @@ qemu start command :
     -net nic,model=ne2k_pci \
     -net user,hostfwd=tcp::5557-:22 \
     -hda /dvdbuffer/i386-install.qemu \
-    -drive file=/dev/sr2,if=none,id=scsicd \
+    -drive file=/dev/sr2,if=none,id=scsicd,format=raw \
     -device virtio-blk,drive=scsicd,logical_block_size=2048,physical_block_size=2048 \
     -cdrom .../some_image.iso
 }}}
 
-With this setup of -drive and -device it is necessary to have a readable
-medium in the drive, when qemu gets started. Else it will refuse to start
-with a message about missing medium or with an i/o error if the medium
-is blank.
+With this setup of -drive and -device it is necessary to have a
+medium in the drive, when qemu gets started. Else it will refuse.
 
 The guest system is accessible via ssh and scp at port 5557 of the
 host system.
@@ -417,17 +415,16 @@ sessions contain ISO 9660 filesystem images, which successively
 build on each other.
 
 So from the view of xorriso commands, the only task which makes
-them differ from sequential media. is to apply optional formatting
-to DVD-RW or BD-R.
+them differ from sequential media, is to apply optional formatting
+or re-formatting.
 
 A special case are BD-R, which xorriso may format but will not bring
 into (pseudo-) overwritable state. Formatted BD-R perform Defect
 Management by default, which checkreads during writing and replaces
-bad block. Nice idea in theory. My practical experience is not so good.
-Ill media stay ill media and should be replaced as soon as possible.
+bad block.
 
-Formatting of unused DVD+RW and BD-RE is done by xorriso automatically.
-Just start a normal write run. DVD-RAM are sold formatted.
+The mandatory formatting of unused DVD+RW and BD-RE is done by xorriso
+automatically. Just start a normal write run. DVD-RAM are sold formatted.
 
 xorriso treats overwritable media with a valid ISO 9660 filesystem as
 appendable media. To make then writable from scratch, apply