Lakewood, NJ, US
This is clearly a hoax! The elastomeric compound was applied only to the top of the board. Therefore, only the top would stretch. Therefore, when released, the board would assume a bow shape (the top is longer than the bottom).
That didn't happen. Therefore, a hoax.
Unless, of course, the bottom side was precoated to save filing time.
Therefore, maybe it does work.
Therefore, my judgement may have been premature.
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