Since it would take little effort to control them, you would be freeing up more of your senses to "listen" and deal with their changing forces. Thus your ability to freely manipulate them would just be natural without giving much thought to "doing" something to or with them.
Thinking to blend and how to "make an aiki connection" and concentrating on THEM... is everything that is wrong with aikido.
Sometimes you seem to be saying contradictory things. Aren't you concentrating on them by "listening" and dealing with their changing forces? Of course when it becomes habitual you don't have to consciously think about it anymore, but while learning how to do this it seems to me that you have to think about them quite a bit, particularly in terms of what they are doing to you and how it feels to have them do it compared to how you want it to feel.
I'd say most people in aikido miss the mark not by concentrating on the other person too much but by not doing it enough. Instead, they just attempt to act out a technique that they have pictured in their mind, and to the extent that the other person does not go along willingly with this idea, they try to force him to do so through various methods that I wouldn't consider aikido. To me, aiki requires moving with another person, and this means letting the other person go where he wants rather than fighting force with force. Of course there is more to it than that but this is a good starting place for most people.