Mob Creeper detection

Back in the very early days of Minecraft, mobs would run away from a creeper that was about to explode. This was helpful if the creeper was creeping up behind you. I completely understand why the feature was removed, with the horrible lag the implementation caused. My idea is to bring the idea back, and potentially without the lag. Instead of having every mob constantly checking to see if there's a creeper, why not instead have a cope in the creepers AI, that when it triggers it causes all other mobs to flee. I don't know if this would work, but in the early days of Minecraft it was helpful