Graham
This is a decision that only you can make, there will be assumptions made about your capabilities but it depends on your conditions and how they effect you on a daily basis, whether this will have an impact.
Whilst you can't really apply statistics to a single claim, I can tell you that the success rate for a hearing you attend is much higher than for one that you don't.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems