I agree. Unless you enjoy the more seamier side to a relationship, or can intelligently channel obsessive compulsive behaviors, it's a more difficult conjunction. If there is a need to change a behavior (ex: drug addiction), this aspect can make that change possible, but there is always a sense of one person over the other, trying to make transformations. There is a need to change the other.
On the other hand, Pluto can make your sex life much more interesting by injecting a lot of passion and sexual games into it.
I have also found heavy Pluto connections to be icy at times. The Pluto person may totally convince you, you don't exist. There alway seems to be extremes involved. Synastry also depends on how evolved a person is generally. Or how well they take to relationships. If the other is immature, or undeveloped emotionally, for whatever reason, this type of conjunction would probably make matters worse.
But, yes, I think there is a compulsion attached to Pluto, although I think Saturn has more to do with karma and past ties.