Minecraft 14w29b bow block breaking glitch

When in survival mode, using a bow and holding it (without shooting) while trying to break a block but stopping near the end still keeps the break of the block, instead of removing the break entirely (you know how you have to hold your attack button to break a block? Well, you can sometimes stop doing that while holding a bow in shooting position and still have it partially broken, and you can break it again quicker.)