What you may be missing is the comment about the fact that the new flash drive with DW5 only boots into Tiger, Leopard and Snow Leopard, while users of the subsequent OS X versions need to boot from the Recovery partition on their Macs, and then use Terminal to launch DiskWarrior from the flash drive. If you use FileVault, you
have to use Terminal too, even if you can boot from the flash drive.
There is an option to create dedicated boot (flash) drives for specific OSes; hence another comment about the need for more than one bootable drive (of any kind) when you have (to deal with) several Macs running different versions of Mac OS X including those beyond Snow Leopard.
The comments are not incorrect, but the issue is with Mac OS X, and not so much with Alsoft. It also underlies Alsoft's choice to move from CD to flash drive as distribution medium, even though you cannot transparently accommodate every possible configuration with a single medium. There's nothing to stop you from installing DW on a HD, be it internal or external.
