If the Buddha were to use that, then He’d have subdued all, the whole world already, no need for anybody else to come behind Him. You see, that’s the difference between a Buddha and a demon. The demon, he uses power just to control people. The Buddha, He had to use reason. If He used His power at all, it was because that person needed it, maybe needed to heal at that time, needed to be awakened from some trouble, like Ananda for example, and to use it to help His disciples in time of need. Otherwise, if the Buddha had used all His power just to bless this person, control that person, then the whole India at that time would’ve knelt at His feet already.