I also take pleasure in the so-called negative power in Grotjahn's work. That is I love his paintings for what they are not. Unlike much art of the past decade Grotjahn isn't simply working from a prescribed checklist of academically acceptable curator-approved 'isms' and twists.
Making checklists of things you're looking for in a person is the numero uno thing you can do to guarantee you'll be alone forever.
There is a very remarkable inclination in human nature to bestow on external objects the same emotions which it observes in itself and to find every where those ideas which are most present to it.