I have been thinking about the meaning of the "permits a rebuttable inference" language used by the judge in the previous post. All that means is that the judge may consider your prior work record as a factor when evaluating your credibility. It is a legalistic way of saying "I can hold your poor work record against you unless I am persuaded not to hold it against you."
Credibility is important because most people who are disabled physically have subjective symptoms such as pain. The judge needs to determine if the pain is as bad as you say it is, and if it limits your ability to work as severely as you say it does. This requires a credibility determination, and it happens in just about every case.
The SSA has a regulation regarding the factors that must be considered by the judge when assessing credibility. Social Security Ruling 96-7p also discusses those factors. Both the regulation and the ruling include your prior work record among the factors to be considered. See 20 C.F.R. 404.1529(c)(3).
This does not mean that if you have a poor work record you will lose your case, or if you have a great work record you will win your case. It is just one of several items that the judge weighs. Having said that, however, when I represent a claimant with a poor work record, at the hearing I always try to explain why it is poor – often it is due to the claimant’s impairments. And when I have a claimant with an excellent work record, I always point it out to the judge.