I read that article you linked Ed, and I found it to be lacking in what studies have told us about the term cult in today's society.
I think a much better understanding of what people term a destructive cult (rather than the old dictionary definition of cult) is the research in sociology and psychology that has gone on for decades since the time of the POW's who came back from North Korea and the mass murder at Jonestown by Jim Jones.
Because destructive cults are not just based on religion but can be formed around other ideologies, political, financial, self-help, psychological, etc. One of the best academic researches on cults was Robert J. Lifton who defined cult well in his criteria of Totalism.
I have posted this on previous threads here that discuss cults.
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" DR. ROBERT J. LIFTON'S CRITERIA FOR THOUGHT REFORM THOUGHT REFORM: THE PSYCHOLOGY OF TOTALISM (New York 1987)
Any ideology -- that is, any set of emotionally-charged convictions about men and his relationship to the natural or supernatural world -- may be carried by its adherents in a totalistic direction. But this is most likely to occur with those ideologies which are most sweeping in their content and most ambitious or messianic in their claim, whether a religious or political organization. And where totalism exists, a religion, or a political movement becomes little more than an exclusive cult.
Here you will find a set of criteria, eight psychological themes against which any environment may be judged. In combination, they create an atmosphere which may temporarily energize or exhilarate, but which at the same time pose the gravest of human threats."CLICK HERE to read the list of 8 psychological criteria
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Not all of the 8 are required for a group to be a totalistic cult.
Regarding Scientology, I can point out what fits -
Milieu control - Scientologists are not supposed to talk to critics, read the internet without the net nanny Scientology filter, or be in touch with former members or "suppressive persons". This keeps them in a closed "bubble" of info controlled by Scientology.
Mystical manipulation - This is obvious in the claims that the levels one can progress to will provide superhuman abilities like perfect health, etc.
Demand for purity - The constant self-checking is there to induce one to avoid reading banned info or being around "suppressive people".
Confession - "Auditing" is the kind of confession that in Scientology can be turned back against a member if they leave the cult. Members don't realize their records are not private. Many ex-members have exposed how their auditing records were used against them especially after they left.
You can go through the list of 8 and see how they fit a cult group.
Many cults I've seen use the ones I listed. Often the confessions can be used to blackmail the member to keep them in the cult.