Dear Martin,
here is my "blueprint" for my BOV shield that I was trying to explain.
As you can see, it lets more air through, but still not enough to totally let the valve open and release all the air before it goes back to the turbo, enough that it would probably avoid a full flutter though, and just do a flutter dump and make it a stuttering hiss instead of a sigh.
One day when I'm not lazy, and can steal Jason's tools again, I'll give it a go and tell you if it works.
Big <3s from your Advan Brother