[SPOILER] Did she tell him?

[Darth Biomech]

Interesting idea. I think in the game world two cortex chips always means two conciousnesses, and you can't just "fuse" them without destroying and reconstructing them.
Or if it were possible, Simon would exist as two interlinked bodies, and killing half of his "body" would be tremendously painful.

Idea is that you make a connection between two minds, that constantly transfer data both ways, not physical fusing of two chips. No conscious gets coin of "left behind", since they diffuse into each other to form a single new entity that is direct uninterrupted continuation of both of them. I believe if this sync will be done right after the copy upload activation, it will feels almost like you suddenly gained second body, instead of sensation of merging with another person, since there will be virtually zero differences between the two of you.
And if you just shut down one of the bodies I doubt it will be painful. Unpleasant, maybe, you'd be insta-losing half of the perception that you grown to be used to, but that's still better than the other option.