Shaco's Permanent Lane Freeze

As the title indicates shaco permanently freezes a lane. I was experimenting with Shaco AP in lanes. When the minions are walking into lane there are 3 melee and three casters, if you place a box directly in front of the caster in the middle and the position of them is not altered until the box terrifies them then they run away but freeze facing away from Shaco. I have replicated this in 3 different games (first two against bots to test and replicate and the last in normals). They are not glitches out to where they do damage because they don't hit or anything but receive damage and still give gold.