Having windows virtual machine (Windows 7, run in Parallels) run from installed SSD
The setup proposed in the setup guide provides a dual-drive environment with a "swapped" system. The faster SSD finally contains the system, some user folders and all apps and the slower but larger HDD contains your user data.

If your Windows Parallels VM is stored in your user folder (the default path is /User/[username]/Documents/Parallels.../) it will run from the HDD. But you can add a folder with your user name in /Users and move the VM image to it or move it to /Users/Shared/.

After deleting the VM from your HDD user folder open Parallels and relink the Windows VM to the VM list. AFAIR you will be asked if the VM was moved or copied. Then choose "moved". After moving the VM image to the SSD all Windows apps as well as the Windows system will run from the SSD.

Finally the root looks like this (I left out a lot of mostly invisible files and folder):

/                                                       \
|-Applications                                           |
|-bin                                                    |
|-...                                                    | 
|-Library                                                |
|-System                                                 |
|-Users                                                  |
|     |-Shared                                           |=SSD
|     |-test                                             |
|     |-YourUser                                         |
|              |-Documents                               |
|                        |-Parallels/WindowsVM.pvm       |
|                                                        |
|-Volumes                                               _/
        |-HDD-Name                                      _
                 |-Users                                 \
                       |-YourUser                         |
                                |-Documents               |
                                |-Library                 |=HDD
                                |-Music                   |
                                |-Pictures                |
                                |-....                    |
                                                         /




The linked guide misses one important step though:

After successfully booting to the SSD and configuring your user, you have to delete the previously copied files and folders on the source disk (the HDD)- except the folder /Users/YourUserName of course.