Just for the heck of it, I did the steps in the article, but I've not yet seen speed improvements anywhere.

In once case, I replaced a newer vmouse.vxd with the older one from the Win98 cab files, but otherwise those were all files that did not yet exist on the system.

The one concern I have is that it was unclear as to which files were supposed to go in system and which in in system/vmm32 so I put them all in both places.

I can tell the files are working because the parenthetical statements are gone from my driver details panels (as the article said they would).