I should start out by explaining that, until recently, I had only ever watched one episode of Star Trek: Voyager in my entire life. That was a recording of the pilot episode ("Caretaker"), some years ago.
Recently, I had a chance to pick up a secondhand copy of Season 4 on DVD at a low price, and I shrugged and went for it. Then I started watching those episodes in my spare time. (Note: I did watch one other episode first. When I saw that S04E01 was Part 2 of "Scorpion," I went to Amazon and paid to stream Part 1 of "Scorpion" first, so that I'd have a clue about what was happening in the second half of that storyline.)
Since then, I've gradually been working my way through Season 4. Things were going fairly well until I watched "Message in a Bottle" (S04E14) and was extremely confused by some of the assumptions that were used to set up the episode's plot in the first several minutes.
Here are five assumptions which caught me off guard as I tried to appreciate the plot, but I'm not asking anyone to justify the first four. Let's just accept them and move on from there, okay?
Until the time of "Message in a Bottle," either it has been utterly impossible for anyone on Voyager to create a full backup of the Doctor's personality software and store it for a rainy day . . . or else they simply never thought to take the trouble?
It is impossible to change this sad situation in the scant minutes left in their window of opportunity to successfully transmit a signal to the Starfleet vessel at the other end of an alien communications network which Seven of Nine has just discovered. (Because that other vessel is nearly out of range of the alien relay station nearest them, and once they are out of range, that will abruptly terminate the possible communications link. I could swallow this part about the impending deadline, actually!)
It is impossible to send a successful signal through the network if it is simpler and less complicated than the format of the Doctor's holographic programming. (I would have thought a simple e-mail could be broadcast just as "strongly," and could be repeated hundreds of times to improve the chances of at least one coherent copy making it all the way through the interference, but what do I know about futuristic telecommunications equipment?)
It is impossible to retain a copy of the Doctor's personality right there on Voyager at the same time that they are transmitting it through the alien network. (Although they do, as we learn later this episode, manage to keep copies of all the medical databases which the Doctor has access to.)
Captain Janeway already knows all of the above, and must be factoring those items into her command decisions, at the moment that she asks the Doctor to volunteer for this special "away mission." She freely concedes that using unfamiliar alien technology to send him thousands of light-years (and hoping that he'll be lucky enough to survive the return trip, as well) is a situation in which "a lot of things could go wrong" -- for instance, his program could be lost in transit. So she's not making it a flat order. But she wants him to do it anyway, and he says: "Far be it from me to turn down an opportunity to become a hero. I'm ready."
With an effort, I can tell myself, "Okay, Assumptions One through Four must be taken at face value, as simple facts which Janeway is painfully aware she can't change in the very limited time available. They don't make much sense, but roll with it and move on! Granting that this is the situation, she has to do something on that basis, right?"
But on Assumption Five, I just felt flabbergasted all the way through the rest of the episode! Why would Janeway be in such a hurry to kick the Doctor out the door? Afterwards, I reminded myself that people who were watching each episode as it came out, all through the show's seven-year run, might have had a different perspective from mine (as the guy who "came in late").
So here is an expanded version of the question I summarized in this post's title.
The Question: Are there crucial factors I don't know about -- something established in one or more scenes during the first three seasons, for instance -- which would cause Captain Janeway's decision to risk sending the Doctor away to the Alpha Quadrant, to deliver a message to Starfleet even if he never makes it back to her ship, to actually make sense as a responsible command decision under the circumstances? (Despite the obviously increased risk of members of her crew later dying from illnesses or injuries which the Doctor probably could have fixed in the nick of time, but which someone else (such as Tom Paris) might not be able to?)
Because right now, viewing it from my perspective as a guy who's only seen S01E01, S03E26, and the first half of S04, before reaching "Message in a Bottle" -- it seems as if Janeway is basically saying, "Hey, I am perfectly willing to throw away our one and only fully-qualified Medical Officer if it means there is at least a fighting chance that he will be able to give Starfleet the simple message that we are still alive and well, albeit sixty thousand light-years away from home and afraid it will take us several decades to get back where we belong!"
I cannot wrap my head around the "logic" of saying that just sending that message, even if the price turns out to be losing the Doctor's services aboard Voyager, is a cost-effective maneuver.
I mean, I try to imagine James T. Kirk making the decision to send Bones McCoy away on a probable one-way mission under similar circumstances . . . and I just can't see it happening. (Even if Bones were an Artificial Intelligence instead of a flesh-and-blood human being, I still don't think Kirk would even seriously consider squandering him on "messenger boy" duty.)
Not if just telling Starfleet HQ where Kirk's ship had gotten to were the only important message to be carried on that trip! But there could be other vital data involved, which upped the stakes and justified an extreme effort.
So that's why I'm wondering, in all sincerity . . . was there something else, not explicitly mentioned in the script of this episode, but established at some other time in the series' long run (before or even after this episode), which plausibly could have been weighing heavily on Captain Janeway's mind at this moment? Something which she felt absolutely must be communicated to Starfleet at the earliest possible opportunity, even at the risk of losing her Medical Officer? (And then expecting Tom Paris to frantically try to take up the slack in that department for decades to come, which even Paris himself felt was not going to be a workable idea in the long run?)