My specialty was voc issues and the return to work of the client-the company I worked for did not deal in medical issues-our services were contracted and paid for by employers and comp insurance carriers-part of my job was to expose and report those slackers you mentioned-I was also required to have a comp adjustors license.
I have worked in construction since about 2003-I got of tired of clients who lied and tried to scam to get undeserved taxpayer supported SSDI and never work again-nearly 35% of clients were like that-it was frustrating...
Some say it can be overdone, but it sure saved a lot of lives and fingers, toes, and limbs during this last oil boom up here.
Either way, do what you love, and sleep well at night.