Cruise's most recent misjudgement - a Scientology sermon on NBC's Today show against the use of anti-depressants - is the latest in a series of increasingly bizarre outbursts that Kingsley somehow prevented during her 14 years as his PR adviser.
Earlier this year, Cruise parted company with Kingsley, probably the most powerful PR agent in Hollywood, in favour of the actor's older sister and fellow Scientologist Lee Anne De Vette.
Once known as one of the most private individuals in Hollywood, under De Vette's management Cruise has become loquacious to the point of absurdity.
From the moment he 'revealed' his relationship with actress Katie Holmes, we have been treated to hearing about a level of intimacy unthinkable in the Nicole Kidman days. By his own admission on Oprah, his enthusiasm for Holmes is 'beyond cool'.
The backlash has already started. People and US Weekly have published polls showing that 60 per cent of respondents believe the relationship is a publicity stunt. And goodness knows what the willingness to talk about his beliefs will do for his current release, War of the Worlds, and the forthcoming Mission Impossible 3. Remember John Travolta and Battlefield Earth?
So is this the real Tom Cruise we are now seeing, untrammelled by Kingsley's professionalism?
Kingsley - whose client roster has included Al Pacino, Richard Gere, Jodie Foster and Tom Hanks, to name but a few - practically wrote the rules for A-list publicity and controlled access with pre-approval for photography and interview questions. In a rare interview, with PRWeek US a few years ago, Kingsley admitted she no longer dealt with one GQ writer who refused to dump an interview with one of Cruise's old classmates.
Now, however, Cruise seems determined to let it all hang out - a ploy that can very easily backfire, as Michael Jackson found out to his considerable cost after baring his soul to Martin Bashir.
The fact is that A-listers are usually as boring, or potentially bonkers, as the rest of us. Kingsley's brand of control lends the best and the worst of them an air of mystery.
When asked once how one gauges how much publicity is too much, Kingsley replied: 'Most of the time you don't know until you have crossed (the line).' A lesson De Vette could apply here.