Shield Speed/Registration

I have played survival since 1.9 quite a bit, and something that has always bothered me about the update was the registration on the shield. Not the hitbox, or the area of its registration, but the blocking registration speed. I have noticed time and time again that when I right click to either block an arrow or creeper, it does not register the block if I do it too quickly.

This is exceedingly annoying, as I will die oftentimes to these mobs when I very clearly had my shield up before the explosion/arrow connected with my hitbox. I would love if the developers could, as a minor update, look over the registration of shields blocking and update it to make it so that as soon as the player right-clicks, the blocking is performed instead of this weird like half second delay in its effect. 

I think this would be an improvement for both PvE and PvP, as it allows for more skill to be used in PvP, and it makes PvE much less annoying if you happen to die even though you were blocking on your screen.