New
#101
That's not the point, those things can happen and be fixed same way in single boot systems too. Thing with separate disks is that there's much less work to replace one system without heavy loss of data on both of them. Of course, there are measures that could be taken to help prevent that, like making full disk backup, leaving data on another disk etc. but it still doubles the work and potential of loosing too much. All that makes investment in another drive (when possible) pay a high dividend.
All of this is even more important when trying a Beta of an OS or widely different OSs, with different file systems like Windows and Linux etc.
Even with W7 and W8, an early alpha version of Win8 manged to wipe 3 of four disks on my computer, twice.