My theory:
Assume for a minute that Davros gets killed. Forever. No Doctor travels back in time and stops himself. None of that. Davros remains dead. Okay?
Okay...
Just before we start though, lets look at the stories up to Genesis of the Daleks, Davros' first appearance. This includes things like the Space Museum and the Frontier in Space, as those stories had Daleks in them.
Right.
Those stories aren't really affected by Davros' death, because in that timeline, different from the one we're in now, the Daleks' travel machines were invented by a scientist: Yarvelling. So Davros doesn't come into it.
Fair enough.
Now, lets take this step by step. First affected story: Genesis of the Daleks. Not much of an effect, pretty much the only deviation throughout the story is the fact that the Doctor and his companions don't get intercepted, and arrive where they intended to. You still with me?
I think so. What do you mean by: "where they intended to"?
The Timelords sent the Doctor and his companions to Skaro, but they had been intending to go to a space station. Watch the Ark in Space, the Sontaran Experiment and Revenge of the Cybermen.
Okay, so in the version of events you're explaining, the Doctor and his chums don't get sent to Skaro, they just continue to the space station?
Correct. This is because Davros had been killed, so the Daleks hadn't been created, so the Time Lords couldn't "foresee a time when they will have destroyed all other lifeforms and become the dominant creature in the universe". So they wouldn't have had a reason to be sent to Skaro. The Doctor and his friends, that is.
Ah.
Yes. So, a thousand years into the future, and the Movellans (robots that were in a war with the Daleks) are just doing what they usually do: exploring planets. The Doctor does the exploring on Skaro, finds nothing, and leaves.
Why was the Doctor on Skaro?
He had to escape the Black Guardian, so he set a randomiser on the TARDIS circuits. That randomiser brought them to Skaro, about a thousand years after the events in Genesis.
Okay then.
Next up: Ressurection of the Daleks. Nothing much happens here, except for the fact that Tegan doesn't leave because there's been no killings to upset her.
Killings?
Tegan thought she had seen too much death, so she left. Because there were no Deaths, not even a time corridor to bring her to them, she wouldn't have left the TARDIS.
Righty-oh.
Revelation of the Daleks: Tranquil Repose is still a burial planet, the dead are still dead, and Davros isn't around to set up the Arthur Stengos plan. For all we know, Teagan might still be a companion, but for now, lets just say she left.
Arthur Stengos plan?
Davros wanted the Doctor to come so that he could exact his revenge. It was a complicated trap, but the ins and outs of it is, the Doctor and Peri never visited Necros. Revelation also started off the Dalek civil war, but because there're no Daleks to fight a civil war, thats not happening. This also renders a few of the Big Finish audio series pointless.
Such as?
The Juggernauts, for one. I think the last 'I, Davros' story is also pointless. Not too sure though.
Cool.
Moving onto Remembrance of the Daleks, and because there's no longer someone to bait with his Hand of Omega ruse, the Doctor collects that, maybe to use at a later point in time. Any questions so far?
Yes. Is there any instance where he would have used the Hand of Omega?
Possibly. He might have used it against the Cybermen, or maybe some planet eating monster.
Of course.
Next up, the TV Movie. In the intro, the Doctor tells us that the Master stood trial for his crimes on Skaro, with the Daleks prosecuting him, and was thus 'exterminated' (he just regenerated). So now, the Master has no reason to regenerate, and he can't make his trap to take the Doctor's remaining lives, meaning that Sylvester McCoy never regenerates into Paul McGann.
That's significant?
Of course it is! In the Night of the Doctor, McGann regenerates into John Hurt, mainly because of him now wanting to fight in the Time War. So McGann isn't around to regenerate, meaning that we could still be on McCoy and Tegan, for goodness' sake.
Oh.
Yeah. Oh. And then there's the Time War, or rather, lack thereof. Gallifrey isn't sealed away, thousands of planets aren't occupied or destroyed. The time lords lived, and the Master and Rassilon aren't ressurected.
That's going to affect the Doctor later on, isn't it?
Yep. Next up: Dalek. Not much happens here, just a few dozen people aren't killed.
Nothing big.
No, this is where it gets big. Let's assume that the Doctor has become Nine. Due to whatever causes.
Ok.
Now, the Emperor Dalek never existed, which means that Rose never had the need to become the Bad Wolf. This means that the Doctor didn't suck/kiss the time vortex energy out of her, meaning that he didn't have to regenerate. Christopher Ecclestone goes for two seasons. Or more, because of what happens next.
What happens?
The Emperor created the Cult of Skaro, meaning that if they didn't exist, neither did their stolen void ship idea. Meaning that the Cybermen didn't come across, and hundreds, possibly thousands of lives saved. Rose also never got sucked across dimensions or into the Void.
So, we still have Rose and Nine?
Yes. The Cult of Skaro doesn't Emergency Temporal Shift to 1930's New York. Not much changes there, except that Caan didn't save Davros (as he wasn't there to save anyway), no new Dalek Empire, no Doctordonna.
Ok. You mentioned the Master not being ressurected. Does anything happen about that?
Yes. Because both he and Rassilon never got ressurected, and Gallifrey was never sucked into a pocket universe or destroyed the Tenth Doctor wouldn't have become the Eleventh, or in this case, Sylvester McCoy wouldn't have needed to regenerate. See what's happening?
Yeah...the Doctor's regenerations were caused by the Daleks. Because they wouldn't have existed, he wouldn't have changed from the seventh incarnation.
Exactumundo. A word I have never used before, and, with any luck, will never use again. After that, there is no new Dalek Paradigm.
Paradigm?
The jelly bean Daleks, from Victory of the Daleks.
Ah, those.
Yeah. We then meet the Dalek parliament, which doesn't exist. And the nanocloud wouldn't have been created, and used against the Church of the Papal Mainframe.
The timelords wouldn't have been in a pocket universe to grant the Doctor another regeneration cycle, as he wouldn't have needed it. By the way, in the Stolen Earth and Journey's End, the Tenth wouldn't have regenerated but kept his face, so that's another regeneration saved. We might still be on the Seventh Doctor, although I doubt it, so let's say we've seen Peter Capaldi become the Doctor.
Ok. Why?
Because the Doctor might've regenerated at the hands of other things.
Right.
Now, here's where your mind gets blown. Because Davros would have never existed, and neither would the Daleks, the Doctor would have had no reason to go back in time and kill him. So he wouldn't have. So Davros would have lived. Meaning that he would have made the Daleks. Meaning that the Doctor would have to kill him. Meaning that he wouldn't have a reason to kill him. Meaning paradox right? Not exactly. Although this might be a valid argument, we must remember that he would have died if the 12th Doctor (whom the Doctor wouldn't of been if it wasn't for the Daleks because no new regeneration cycle) hadn't gone back and given him his sonic screwdriver. Therefore, Davros would have most likely died anyway.
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You're confused, aren't you?
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Oi, wake up.
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