Sometimes modifications are necessary to get people to a point where they can do the exercise without injury. For instance, when I teach yoga, I do all kinds of modifications for people based on age, disability, flexibility, and sometimes weight. It's good practice, as long as the person is actually getting a good workout still. That said, I doubt a workout designed by a fat for fats is any kind of workout at all. That said, I've spent a lot of time adjusting pigs and setting up blocks for them and showing them how to use straps and how to modify poses for their girth, and I've only had TWO out of dozens complete the 10-course beginner series I teach. They pay for a pass for all ten in advance, and the room smells better, so I can't complain, but I don't know why I try so hard.