I don't yet need PIP, but in researching the Bus Pass concession and Blue Badge entitlement criteria I came across a very negative (good for an appeal) remark in government documents about the ability of PIP assessors. From the Disabled Persons Transport Advisory Committee of Aug 2018 ( https://www.gov.uk/government/publications/dptac-position-on-extending-the-blue-badge-eligibility/dptac-position-on-extending-the-blue-badge-eligibility ) Paragraph 7 says the following! >> There is a perception that PIP assessors generally understand physical health conditions much better than non-physical conditions such as mental health, autism, dementia or cognitive difficulties. We don’t think either type of condition is necessarily more difficult than the other to assess. However, many health care professionals lack the necessary understanding of mental health conditions, autism, dementia and cognitive difficulties. << The whole piece is worth a read if you are up to it. It doesn't carry the weight of a legal opinion but it does undermine the general ability of PIP assessors to remark on hidden issues.