Allowing dos and regedit in a restricted Windows

See http://blacksun.box.sk/tutorials/format.php3?file=windows.html for some very cool tactics.
A very simple tactic I found after accidentally locking myself out of dos and regedit is to open notepad and type the following:
REGEDIT4
[HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionPoliciesWinOldApp]
"Disabled"=dword:0
[HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionPoliciesSystem]
"DisableRegistryTools"=dword:0

Save it as something.reg then run it. Simple.