Plagiarism - "A Moron in a Hurry"

Came across this great legal term on TV:

“A moron in a hurry” is a hypothetical person against whom a claimant’s concern might be judged in an English law civil action for passing off or trademark infringement. The expression is used to reject a claim that two items could reasonably be confused by a passer-by (i.e. that even a moron in a hurry would notice the difference), on the grounds that the items are so different that the goodwill and brand of the claimant’s item cannot genuinely be affected by the existence of the other."

Good litmus test regarding copying/ rip-offs/ passing-off:
“…even a moron in a hurry would notice the difference…”