Nicole Kaeding of Cato has an article on the SSD system heading for bankruptcy. I can tell you from my experience that a week does not go by when someone doesn't come to me looking for work and saying something like, "I am on full disability but I am fully able to work. However, I can't take any pay because that would screw up my disability payments. Can I work for you and have you write my payroll checks to my wife?"
The easy answer to that is "no". With a backlog of 25000+ people who want a job, why am I going to help them cheat, particularly when it would be me taking the legal risk?
I once had an ex-employee who was applying for a SS disability. You may not understand that for many folks, getting a Social Security lifetime disability is like hitting the lottery. This employee knew that if asked, we would have to tell the SS investigator that she seemed fully able to do her job and never demonstrated any reduced functionality. So to pre-empt that, she and her attorney sent me a letter saying that if we in any way testified to her being able to work and prevented her from getting her disability payment, she would tie me up in court for years, suing me for sexual harassment, discrimination, and everything else she could think of.