Tehcnically Simple would kind of get the Eviolite boost. This is what would happen in an example.
Defense 100 Sp Defense 100
Lets say you use Stockpile twice, which would make it.
Defense 300 Sp Defense 300 ( Due to Simple )
Then Evoilite would make it
Defense 450 Sp Defense 450.
So you're still getting the extended boost, you see?
Instead of it going to 200's and finishing at 350's.
You're going to the 300's and finishing at the 450's.