How can we (or should we) discern a variant between Q2 and F1 that derives from an authorial characterization from a variant that derives from what might be an error, perhaps by the transcriber or printer? Specifically, I can't see how Ophelia's exit after her soliloquy at 3.1.150-61 (see p. 7) could be anything other than an error. Polonius's direct address to Ophelia comes seventeen lines after her "exit," which seems to me to make it very hard to imagine the lines directed to Ophelia as she is exiting.
Is it the editor's job to "emphasize certain character traits" (p. 11) in the selection of one text over the other? When an editor chooses between two variants, might not the decision be based on which is most likely closest to what the author wrote, rather than closest to the editor's desired interpretation of the text? Which comes first, the text or the interpretation?