Honestly, that's not luck. Aldo got timed overcommitting against a precision puncher with power and paid for it. That's not to say the result repeats itself every time they meet, but McGregor didn't throw a hail mary punch with his eyes closed; Aldo screwed up, McGregor saw it and made the most of it.
Also, please no instant rematch, Frankie's been screwed enough. He's 5-0 since the dec loss to Aldo and finished two top 5 featherweights. That's more than anyone in the division has done to earn a title shot.