[C21] Replication Technique demonstrate target misleads opponents.

I cast [[Replication Technique]] I choose a target, I then choose to demonstrate and copy it and allow an opponent to copy the spell. The issue is that lets say I copy my [[Propaganda]], then the copy my opponent gets is also targeting my Propaganda. This is an illegal target (card is copy target permanent you control), so the opponent should change to a permanent that is their own, but more times than not they don't. The card itself functions correctly (i.e. the copy fizzles as the target is illegal), but I can see why my opponents get confused.