The reason they are linked is that Atos, a sponsor of the Paralympics, is the company which the government uses to do the assessments of people claiming disability benefits.
Problems with the assessments have been highlighted in the news a number of times. The extreme end is that hundreds of people have been declared fit for some form of work and died shortly afterwards.
Where appeals are concerned, if someone goes for an appeal with no help, there is a 40% chance that the Atos decision will be overturned. If they get help from, for example, the CAB there is a 70% chance of the decision being overturned. Those numbers alone give some indication that either Atos are not assessing people properly or are being too strict in the assessment.
Oh and to put a bit of icing on the cake, I seem to recall reading recently that further changes to benefits for the disabled, which will be applied from next year, will affect at least one of the GB athletes taking part in the Paralympics.
And finally, just to give another bit or perspective on all of the disability claims, the DWP themselves put the level of fraud for Disability Living Allowance at 0.5%. That, in money terms, is £60 million, and the fraud figure for incapacity benefit fraud is another £20 million (0.3% of the total). Those figures are for 2010-2011.