Do those who love sinners and hate sins actually switch all the time from one to the other?

OLD TESTAMENT - Ezekiel 8:18 states, "Therefore I also will act in fury. My eye will not spare nor will I have pity; and though they pray in My ears with a loud voice, I will not hear them."

NEW TESTAMENT - Ephesians 2:2-3 states, "And you were dead in the trespasses and sins in which you once walked, following the course of this world, following the prince of the power of the air, the spirit that is now at work in the sons of disobedience—among whom we all once lived in the passions of our flesh, carrying out the desires of the body and the mind, and were by nature children of wrath, like the rest of mankind."
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Do those who love sinners and hate sins actually switch all the time from one to the other?

Yes if you suppose that love and hate can be separated.  Even if it is not clear-cut it is still possible for a person to intend to love and intend to hate and thus the one who claims to love sinners and hate sins could be switching intentions all the time. You do not blame the sin or declare it responsible when somebody is murdered or raped. You blame the person and declare the person responsible. It is sinners that go to jail not sins. It is criminals that go to jail not crimes.  In fact if people are switching they are not separating the sinner from the sin as much as they say.  

Religion commands us to love the sinner and hate the sin. This principle is about their display of self-righteousness and not about the reality. It cannot if ever be put into practice.

Sin is an offence against God or to put it another way, it is breaking the law of God. It's a crime not against the civil law of the land but the civil law of God. Crime is that which cannot be tolerated. Thus Christians worthy of the name will not tolerate sin. They will vote so that the law of the land does not tolerate it either.

Do you love your father when he does acts of great evil?

You may love your father but when you think of him as evil or sinful you will switch to hate. To hate sin is always to hate sinners. Though we speak of a sin as if it is separate from the person, what we mean is we are thinking of the person as a sinner. It is personal.

It is possible to feel both love and hate for a person. But feeling love for them and feeling hate for them does not mean you hate or love them or both. It is what you do that determines that. If you feel great love for somebody and are hurting them and don't intend to stop that is hate.

So when love or hate is seen in terms of doing rather than feeling, love the sinner and hate the sin is incitement to hatred because you have to hate the sinner when you don't love him.

When people say they love their evil children but hate their sins what they often really mean is that they feel love and feel hate for them at the same time. That is outside the scope of love the sinner and hate the sin. Often they mean they love them most of the time but when they think of them as sinners they hate them. So it is switching back and forth. To ask somebody to hate sin is always to ask them to hate the sinner.

If you cannot love the sinner and hate the sin, you are going to do one of these instead of the other. Perhaps you will love the person one minute and hate them the next. If you cannot love the sinner and hate the sin, there is no way the principle should be used as follows, "People cannot accuse us of inciting hatred against those sinners as long as we say we love the sinner and hate the sin." You are guilty of inciting to hatred.

When you change the wording of the principle to its true meaning, "Love the whole person and hate the sin they commit" you see how contradictory it is. The person has to be at least partly hateful if she or he is a sinner.

When you tell a Christian you love him but hate his faith see how he feels! See how he starts to admit to himself that love the sinner and hate the sin makes no sense. The principle is itself a principle of hate. It trivialises hate and urges hypocrisy. And especially when the Christians own book, the Bible, denies that God punishes sin not sinners. It makes it clear that God is vindictive and angry with sinners. The principle is pure hypocrisy.