SSD - Sys Prop, Environment Variables, or Reg Hack to move Defualt Dir

I've read several sites with recommendations on moving the C:\Users, ( User Folders - Change Default Location) C:\Program Files, and C:\Program Files (x86) for Window 7 (Change Default Installation Directory In Windows 7 & Vista). Some discourage moving the Program... directories (Sean's Windows 7 Install & Optimization Guide for SSDs & HDDs).

I noticed that by right clicking "My Computer" and selecting "Properties" you get to "System Properties" and under the "Advanced" tab, there is a button for "Environment Variables". Clicking on this button brings you to a screen which allows you to change the path, or add additional "Environment Variables".

If the path is changed in the Register

Code:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion

for both "C:\Program Files", and "C:\Program Files (x86)" I'm wondering if these variables change automatically or need to be changed manually. It seems that by changing them through the "System Properties" you only change the variables for those listed.

I'd like to move at least the "C:\Program Files (x86)" to the HDD (D:\) rather than keeping it on the SSD (C:|\) which is the Boot drive. Anyone have some deeper thoughts on this?

It defeats the purpose of getting a much faster SSD if you anchor the programs on the slower HD. Better to get an SSD large enough for your programs, then if it fills up uninstall and reinstall lesser-used Programs to your data HD.

Some have had problems with moving User folders to the HD so an easier method is to set up a parallel set of User folders on the HD then rightclick each to link to the related Library - Include a Folder - Windows 7 .Forums

Of course you can try it but be prepared for issues and possibly needing to move them back. I had unresolvable permissioning problems running my Downloads .exe's from D:
User Folders - Change Default Location
User Profile - Change Default Location