The link to your blog is broken
What we ended up doing (both in 8.8 and now on 9 since 9's HII isn't ready for prime-time yet until some stuff is fixed), was to use the most excellent copydrivers tool, and within the files that it downloads is the provisioning agent installer. Then we just run it as a local execute install since the installer is now local to the computer...
we are facing same problems - I have to deal with 70+ remote sites.
I didn't get what you mean when saying "was to use the most excellent copydrivers tool" ?
May I aks you to go more in detail?