I remember a guy in Kauai surfing (or trying) with one of those boards (Tomo boards for kitesurfing), I looked at it and it looked so small, never thought you could surf on it.
He was finishing surfing in Tunnels Beach (surf breaks were 400 meters away from beach). Those wave are reef waves, fast closeouts and with that board you would not be able to outrun the wave if you want to escape it (very low volume board), also the popup (standing on board) has to be dead on balance and center ... there is no margin for error.
but I didn't see the guy surfing with it
you don't want to end up like this guy: