Good test there @Turtle. Perhaps you should have included a jar of Nutella to better simulate conditions.
Problem I find is when it's low tide with a couple of sand bars exposed. Hard for the paper to break down then.
Sand bars???? Should that have been sand bars with Blind Mullets exposed?
There's a public Water Park up this way that is sometimes closed for cleaning. You just know that "cleaning" is code for Blind Mullet removal time.