Vista - Restricted Sites List fix: File question

In the excellent tutorial "How to Fix a Slow Windows Mail", found at the following link,

Windows Mail Slow

a pair of files are offered for download under the "How to Fix the Restricted Sites Issue".

By any chance, are these two files reversed? I note that the one intended to fix the problem, "SlowWinmail_Fix.reg" eliminates the registry entry, while the one intended to remove the fix, "Undo_SlowWinmail_Fix.reg" installs the registry entry with value "1".

This issue was discussed by "Javacool Moderator" on May 19th, 2007, 02:05 AM at the website

SB restricted sites slows up Vista Windows Mail - Wilders Security Forums

(which I found from a link in this forum). The code from his fix is:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_MIME_SNIFFING]
"winmail.exe"=dword:00000001

The above code matches the Undo file mentioned above, while the "fix" file mentioned above ends up with the following:

"winmail.exe"=-

I would greatly appreciate clarification of this. Yeah, I know, it's an old problem fixed long ago, but I have been suffering all this time and would like to be done with it!