“(4) In assessing the extent of a claimant’s capability to perform any activity listed in Part 1 of Schedule 2, the claimant is to be assessed as if— (a) fitted with or wearing any prosthesis with which the claimant is normally fitted or normally wears; or, as the case may be, (b) wearing or using any aid or appliance which is normally, or could reasonably be expected to be, worn or used.”
“in assessing the extent of a claimant’s capability to perform any activity listed in Part 1 of Schedule 2”