I tried that with round disk traps last year. Not as creative as you. I thought it was bordering on legal so didn't leave out there to long.I had No luck either.
Looks like it protects trap pretty good would be good late in season on opening holes too.
Does it still fold up?
Saw a guy replace his flags with floats said he did it incase they went through it floats them in hole. I asked if he ever tried to see if they worked. He replied not yet. Didn't look like it would work. I still liked look of the floats though.