They have worked hard to do so since. Most of the big houses have their own PR departments and make extensive use of outside consultants. They still do not like talking about specific deals, but they are much more willing than previously to share their expertise and offer their thoughts.
They have worked hard to establish personal links between their top people and journalists. Mostly this has been quiet and scarcely visible, but it indicated a major cultural shift.
Or so at least it seemed. One of the firms leading the charge has been Texas Pacific Group. A couple of years ago it received an unjust pasting over the Gate Gourmet strike at Heathrow - the one that hit BA's catering.
Since then, the firm has worked hard to stress that it is not an opportunistic financial engineer, but a firm that specialises in operational excellence.
Politicians, journalists, leading City accountants, lawyers and bankers have been targeted with lunches, breakfasts and dinners, both in-house and at some of London's better restaurants. The consistent message was that this was a firm focused on turning around businesses by improving the quality of management.
When the Bradford & Bingley rescue was first mooted - in which it quickly agreed to provide a major tranche of new capital - the subtle overlay was that this was also a firm with a civic responsibility. And then, just as the most resolute doubters were being turned around, it abruptly walked away - with only the most cursory of explanations.
In so doing, it demonstrated all the ruthless single-mindedness that has made people uneasy about private equity firms in the past. It cut the ground from under not only the troubled bank, but also those who had been targets of its PR. They will not easily be won over again.
Anthony Hilton is City commentator on London's Evening Standard