The article you linked doesn't make a case for disassociating guilt but for people "to start exploring that feeling". Nearly the opposite.

The article I linked is part of a series, the purpose of which is "To explore a whole slew of tools for removing guilt-based motivation and replacing it with something that is both healthier and stronger." I believe that dissassociation (in the way described in this post) could be a great tool to help with ultimately removing the emotion as related to motivation.

I'm not sure whether I can make that point easily in text where you don't see the basis but I will try: If you treat someone as separate from their emotions you treat them as a object that's driven by external forces instead of being a subject.

First, people are objects driven by both external and internal forces. To treat them otherwise commits the fallacy of libertarian free will.

Second, it's possible to view someone's demons as a part of them, while personifying those demons. I have visualizations I use where I imagine hate as an ugly, green substance inside of me that I can push out and throw away. On one level, this is "disassociating" the emotion. However, this doesn't mean I'm not acknowledging ownership for the emotion - rather, I'm recognizing my ability to use other parts of my psyche to control the hatred. I think your model of "disassociated" = "agentship" is limiting. Using your imagination to see yours and others in different light can be a tool FOR agency.