This is a stupid marketing term by the company in question. This thing has been possible on Unix-y systems for quite a long time with software RAID (DM on Linux, SVM on Solaris, etc.).
For example, take two disks (sda and sdb); create two partitions on each (sda1, sda2; sdb1, sdb2). Mirror the first partition on the drives:
$ mdadm --create /dev/md0 --level=mirror --raid-devices=2 /dev/sda1 /dev/sdb1
And then concatenate the the second partition on each drive:
$ sudo mdadm --create --verbose /dev/md1 --level=linear --raid-devices=2 /dev/sda2 /dev/sdb2
Ta da. An SVM example under Solaris is left as an exercise for the reader.
Just because the typical home user does not know how to do this under the most common operating system available does not make it novel, nor make it worth creating a new term for it IMHO.