Capacity vs performance
WHO-ICF: capacity is what you can do unaided in a standard setting; performance is what you actually do with treatment, aids, and environment.
Trap to watch
Mitigated-state trap — IP usually assesses treated performance; ADA/UK/EEA guidance often looks at the unmitigated baseline.
Evidence the workspace should capture
State which axis the assessor used, and keep both scores if they differ.