I took my mum to hers last week, she wanted moral support as she had never been in the job centre place, it was fine...the lady who interviewed her was very polite and understanding, she went through a computer questionnaire with my mum...when it got to the bit about having regular job seeker interviews she decided there was no way mum was going to be able to return to work, she's 57, and reminded us that at the moment attendance was voluntary anyway, she intended to make a note on the computer saying that it was unlikely she would return to work and that due to her disabilities keeping appointments maybe difficult....after she told us that it would be highly unlikely that mum would be called again for any further interviews...bless her she even gave my mum information on the Expert patient programme and the name of a local acupuncturist...it really wasnt threatening at all, they ask you to elaborate on what having your health problems means in a practical, emotional sense etc. So by the time you run thro EDS and Chronic pain and any additional health problems you are fairly covered on it all. the lady offerred advice on checking whether all the right benefits had been awarded, and spoke about dla, registering disabled and blue badges. To be honest, this was nearly the same as my interview and I didnt have to go back either...dont claim now as illhealth retired.
the only negative thing that was said, really effects people from October who apply for benefit, apparently the interviews are going to be mandatory and harder!
Hope this helps, it honestly isnt a real heavy thing and I'm sure you will be fine
PS I'm guessing the booklet you filled in was the personal capability questionnaire, it would be a good idea to read thro a copy of it and take it with you if you think you may go blank ...like I do
Also this has no effect on your DLA...that is awarded purely for your disability, this is about whether they could 'assist' you in any way in returning to work and checking you are on the right benefit.