That statement doesn't mean throw out everything because fuck it. It means if a situation arises that is deemed better than sticking to past precedence's isn't mandated. Seeing if he can become a two division champion is more appealing, more historic, and a better option than repeated a fight that happened less than a year ago and ended in a 13 second knockout. Aldo isn't going anywhere, if McGregor loses then he can go back down and face Aldo again, there isn't some time limit on that fight that it can't wait.