Personal testimonies do not always shine a light on what is really happening with policies or institutions, as the recent row over one woman’s cancelled operation has demonstrated.

However harrowing one person’s experience may be, it could be the exception and obscure wider truths that can be confirmed only by solid, objective data.

Anecdotal evidence can undermine good decision-making and distort effective administration. Yet its power should not be underestimated, as it can also reveal hidden realities and confound prejudices.

So it was at the launch of Homelessness Link’s manifesto to end homelessness, when we heard from men and women whose lives had been pulled back from the brink by the work of frontline agencies in the field.

The government rightly gave early priority to tackling rough sleeping. Much has been achieved, albeit slowly, given the complex nature of the problem. Homelessness Link reminded us that there is much more to single-person homelessness than rough sleeping alone and that many of our prejudices about it are wrong.

We heard from someone who, for me in any event, represented the face of rough sleeping as I have always understood it – an older man, poorly educated, who almost certainly began with few chances in life and never got more than a toe on the ladder.

His story of struggle and gradual recovery was powerful enough. Yet the real slap in the face was the evidence of two women, both educated professionals, whose comfortable, even affluent, lives disintegrated about them. One spoke about how stress tipped her into alcohol and drug abuse, driving friends and family away until she ended up on the streets. The other described snatched moments of sleep in her car, terrified that she would become a target for theft, assault or rape.

Looking at them in the opulence of the House of Commons dining room, articulate and immaculate, it is impossible to guess what they went through. Yet thousands like them continue to see their lives collapse, with homelessness a key factor among the many triggers that combine to cause havoc: mental illness, drugs, prison, relationship breakdown, domestic violence and alcohol.

Homelessness Link’s manifesto reminds us of how much more needs to be done to build on the Rough Sleepers Initiative. Its 10 points include the need for further reform of homelessness law; a further expansion of housing supply so that single homeless people are not squeezed out; more integrated working, especially when people have multiple needs, and with drug and alcohol issues; greater recognition of homeless people’s health care needs; benefits, advice, cultural requirements, and an emphasis on citizenship rights and inclusiveness, including the way these relate to refugees and migrants.

These are ambitious, even noble, aspirations, and important ones: sometimes we need to lift our heads from mundane practicalities to get some vision into policy. But there are plenty of simple, practical things that could be done to reduce burdens on vulnerable people and give them a better chance of coping with their lives. A regional rent deposit scheme, for example, would allow hostel occupants to move into private accommodation. We need to cut housing benefit delays – a subject very dear to my heart, given Westminster council’s dismal record. A tenancy support programme could ensure that former homeless people get help when they need it – so that their shot at a settled home does not unravel because of some minor bureaucratic difficulty such as form-filling. Taken together, these initiatives could make a profound difference.

I was already convinced of the need to look afresh at single homelessness and rough sleeping, to build on the success of the Rough Sleepers Initiative. Homelessness Link’s manifesto, backed by the raw power of the survivors’ stories, confirm to me that there is a whole new agenda to embrace.