Personally, I find the idea of telling the PHP server to load an invalid extension (which forces error checking, logging, etc) to be ‘not optimal’, to use your language.
If you’ve got servers that use all of ini1, part of ini2, and part of ini3, what you actually have is
All Common Elements in ini1.
Elements specific to one type of server in ini2
Elements specific to the other type of server in ini3.
No overlap at all. And yes, there are more ini’s to modify - but thats what you get with having multiple server configurations.
To each their own, I suppose.