I find it hard when people talk about being unfit for work because to me that implies a permanent state of being which is frankly negative. We have a benefit system and a generation of sick people who have written themselves off in the long time when this is not necessarily the case. I much prefer to think of people getting ready for work, even if that process will never be successful. To understand this, we must go back to the sick role.
I see sickness as something with three possible outcomes, it is either something who recover from, something you die from or something that becomes stable and manageable where it becomes an impairment. The later has only recently been acknowledge and demonstrates and acknowledges the employability of people with impairment as well people. The sick role states society will accept periods of sickness so long as people did everything they reasonable can to recover. Therefore periods of sickness are or should be periods of activity in terms of recover to a full state of health or a state of impairment, not periods of inactivity which the middle class media seems to be suggests.
If someone is sick then me question is what are they doing to reach a point of stability as they get ready to work.