I used to think the "build in a trash bag" thing was a myth, or something to just scare newbies.
Then, I actually saw a guy blow a plane to bits at my field, and pull a garbage bag out of the wreckage. [X(].
Personally, I'm a bit more optimistic than that.
I've always wondered about the parachute thing. The military has used them to recover some RPV/target drones at various times in the past, and in theory it should work. And like Dennis, I saw ads for such a setup years ago, but never saw one in action, and I have no idea if it worked well, or what would happen if you deployed the cute in an actual "I'm going to crash" dive, or when almost inverted, etc.