[Zope] INSTANCE_HOME and products that patch Zope

What do people do if they are using a multiple-instance Zope setup (INSTANCE_HOME, etc.) and want to use a product that patches Zope code, such as TransparentFolders? Are there just not that many products that do that? Do they just install the product in SOFTWARE_HOME? In other words, the multiple-instance mechanism supports Products and Extensions in each instance, but not Zope patches. Seems to me you'd want that so you could experiment with patches (including, perhaps, hotfixes) without interfering with the production Zopes running off the same SOFTWARE_HOME. -- --- Mitchell