Weighted pressure plates (Light)

NOTE* This bug works in all gamemodes* The weighted pressure plate light or Wppl does not work correctly im not stepping on it like many others are reporting. I have 3 different items on the Wppl and it works fine. I have 3 same items on the Wppl and it does not work it only sends a 1 redstone pulse. I would like to know if this is a bug or a feature. Ive included 2 pictures below the first being of the 3 different items and it working and the second of the 3 same items and the wppl not working.