Looks like that particular hook in the vid didn't need to contact, if it did. Jab Jab adjust and right cross is a nice trap to an awkward lefty. I like watching in fighting for reactional combos. You see a few in the lighter weights that are body or arm reactions going up or down to cover from being hit and the attacker knowing instinctively that theres an opening and fires into the openings continuously. Mab and Morrales had some of those moments nose to nose. MAB would even use an extended arm on a turn to get in the way as they shifted bodily to spot what opening it created. A lot of that off the cuff stuff comes from not fearing being hurt but you could copy it knowing the reaction you'll get as a set up.