While I agree that the attempts of some of these pseudo-trad priests to put traditionalists in their place and get them to check their egos, borders on slander a la Jorge, and that Fr. Ripperger has been one of these, I don’t find that he blames everything that goes wrong in your life on demons.  In fact, he states the world and the flesh are just as much the cause of sin as is the Devil, in one of his most popular early talks.  “The Devil is not under every stone.  He’s under every other one.”

I've listened to many of his talks, and while he does pay lip service to the notion that not every ill is caused by demons, his emphasis is such as to convey precisely the opposite.  He gives the IMPRESSION that nearly every negative thing in your life has a demon behind it.  He has like a 10-page-long list of different spirits, for just about everything, including physical ailments like "GI Problems".  And he even hints at this in the statement you made that the devil is under every other stone.  It engenders a mentality that can quickly become very unhealthy.  So my car broke down ... could it have been a demon?  I lost my job ... demon?  I developed GI problems ... demon?  Even IF a demon were proximately responsible, it is GOD WHO PERMITTED IT, and therefore my car breaking down or my GI problems are GOD'S will for me.

We can command them to leave only in the name of Our Lord ...

No we can't.  Because we don't have authority over them, we can't command them.  It doesn't matter if you add "in the name of Our Lord" ... it is still you who is attempting to do the commanding.

Where did I say that?  We pray to God, Our Lady, the angels and saints to "deliver" us and bring us relief.  But we do not command demons whom we imagine to be the cause of such things.

While there are some prayers in his book that the faithful may use, the problem is with the prayers in there where the faithful are issuing commands to the demons.  Father bases this on a mistaken principle, that has no basis in Traditional Catholic theology, that we may issue commands to demons if they are afflicting those over whom we have authority.  But the Traditional teachers say you should have authority over the DEMONS that you're attempting to adjure (issue commands to).  So, the analogy I make is that I see a thief trying to steal my car.  I run over there and order him to stop because it's my car.  Chances are that he'll just kill me and continue taking the car.  Simply because we have authority over the individuals being afflicted by the demons, it does NOT follow that we have authority over the demons themselves.  St. Alphonsus said that one should be an Exorcist (i.e. have order of Exorcist or higher).  Demons are in a state of rebellion against God's authority.  Now, if we pray to the Guardian Angels of those who are under our authority and are being afflicted, those Angels WILL in fact heed our authority because, unlike the demons, they recognize and respect our authority, since it is the authority of God Himself as communicated to us.

While one might speculate that this might be the case, I have found no principle in Traditional Catholic theology demonstrating that our authority over afflicted individuals puts us in a position to issue commands to the demons themselves.  Father Ripperger at one point stated that he hasn't seen the demons engaging in any "retaliation" as a result, but that's a very anecdotal consideration.  I have heard some individuals stating that they seemed to experience or sense an increase in diabolical activity ... though that too is anecdotal.

In any case, I have yet to find a theological principle to back this up.  There's a huge danger here if he's wrong (and I think he is).  Why not just pray to Our Lady, the Terror or Demons; demons flee from her presence?  Why not make use of the Sacramentals, Holy Water, Blessed Salt, Saint Benedict medals, etc.?  Why not adjure the Guardian Angels of those being afflicted?  These latter will in fact heed your authority and are perfectly capable of shutting down the demonic activity?  What's the upside of issuing direct commands?  None.  What's the downside?  It could be catastrophic.

Now, Father Ripperger asserts that the principle can be found in St. Alphonsus, but I reviewed the citation in Latin and found that he was seriously misinterpreting it.