Mandatory reconsideration - how much detailis needed?

Hi there - looking at your excellent guide on MR and appeals and challenging a medical report. Can you challenge the report at the MR stage or is that more at appeal? How much detail is needed at MR if it is difficult to get evidence (the joy of managing long term health conditions and the medical lot just letting you get on with it)? Given how stressful it is and how few decisions get overturned at MR stage is it better to do less just to get you to the next stage of appeal? I know that in itself is long and stressful though.

Anyway - interested in your thoughts.