I'm not sure if it's wise to publicly post this "taking advantage of that freedom and focusing instead on podcasts or reddit for 3 days to avoid 3 hours of writing unit tests."
If your results-based performance is deemed adequate, that means either the company is getting good value for the money they pay you, or they have a broken performance management system.
ADHD doesn't really factor into it. If ADHD leads an employee to have subpar performance, they will be fired just like anyone else.
Caveat: the best companies think like this. Most don't.
I've worked with people who come in late, leave early, and make huge, disruptive, positive impact as well as slow, positive change.
I've also worked with people who work 15 hour days who don't work well with others and are constantly picking up after themselves as their silo'd work breaks daily (yet from management's point of view, everything is running smoothly not realizing they have a giant bus factor on their hands).
So ya, nothing to do with hours worked and, if you're working for a decent company, there should be reason not to be upfront about this.