"Unfortunately going from just the last email in the thread to being able to reconstruct the entire thread would be exceedingly difficult."
Good. That's the way it should be.
"The whole magic of the site is being able to have the experience of looking over other people's shoulders into their inbox, and seeing how they actually talk with one another when they're not on stage."
What you call "magic" is a blatant and disgusting violation of my privacy. Those messages are "not on stage" for a reason; if I wanted them to be "on stage", then I would put them there myself. You have no business "looking over [my] shoulder" at all, let alone inviting everyone else in the world to do so.
Good. That's the way it should be.
"The whole magic of the site is being able to have the experience of looking over other people's shoulders into their inbox, and seeing how they actually talk with one another when they're not on stage."
What you call "magic" is a blatant and disgusting violation of my privacy. Those messages are "not on stage" for a reason; if I wanted them to be "on stage", then I would put them there myself. You have no business "looking over [my] shoulder" at all, let alone inviting everyone else in the world to do so.