Based on crippling the product for those who pay for it. I.e. there will be those who will simply skip it because of DRM altogether.
In addition, some skilled pirates will remove DRM and provide that product without crippling for everyone else, and there will be those who otherwise could buy it, if it would have been DRM-free, but because it's DRMed they will pirate it instead.
No, that's not correct. It's based on research how DRM reduces sales. An opinion on the other hand is the idea that crippling products increases sales. That's exactly what was called digital Lysenkoism.
Based on what?