Humperdinck: "Now, if we only had a wheelbarrow..."
I look at previously unmentioned assets in Doctor Who...with an eye to storming the castle of dimensional retroclosure.
Assets...we should be listing.
Fob watches. Time Lord essence can be stored in a fob watch device. It can be stolen away. Therefore...it is not an intrinsic thing. In the Christmas Invasion and in Human Nature...there was the presented idea that this essence could be used as a power source by another species. Also, we know it is not intrinsic to Gallifreyans. We know that there are Gallifreyans who are NOT Time Lords...one of them married the Doctor's all too human companion, Leela. If Susan was the Doctor's granddaughter...biologically Gallifreyan...and we have no canon reason to doubt she was...she married David, a human. Jenny is biologically a Gallifreyan...two hearts...but she's not a Time Lord. Because becoming a Time Lord involves sharing...pain, memories...history. Sort of like Ten and Ten 2 share...history, memories and pain.
The Master married a human woman...but then, the Master fails to regenerate. Maybe he couldn't...maybe he wasn't a Time Lord anymore.
Handy Spare Hands. The handy spare hand was in the Master's possession at a very crucial time...just after he, the Master, had regenerated. So, should he have cut off his own hand...he, too, would have a handy spare hand. Also, the mystery of why the Doctor was toting around a handy spare hand, is still a mystery. You can't say it was so RTD would have it later. The Doctor must have had a reason for keeping it close. One thing we know it does is get excited about other versions of the Doctor close by...it got all worked up over Jenny in the time stream. Maybe the Doctor was using it to avoid himself. Or maybe he had some real use for it...like creating a controled, rather than instantaneous, biological metacrisis.
Biological Metacrisis. We think we know what this is. We got a spare Doctor from the spare hand. And for a time we had a Doctor/Donna and it was good. But there has never been a human/Time Lord metacrisis...why? "Because there can't be." Why? Because it will kill Donna...she will burn, the Doctor tells her family. Why? Because her brain can't handle all of that knowledge, apparently. However, Ten 2 has a Time Lord mind and so, HE can handle things. Why? Uhm...this is where we start all of our assuming. Because we don't know why Ten 2 is human enough to die and not regenerate, but at the same time Time Lord enough to think big thoughts. This is because we don't know anything about biological metacrisis. It's something that has happened before though...just not with a human.
The Master: Nobody in fandom questioned the return of the Master. We all knew he was dead. Had to be dead. All of the Time Lords are dead. Also, he was a corpse before the Time War...and a plasma snake creature...and...ashes. And he just keeps renewing himself. The Master always comes back, just like the Doctor always wins.
What does he tell the Doctor? "The Time Lords brought me back, gave me a new set of regenerations and made me fight their war."
And we all just nod and think...okay! Nobody in the fandom balked. Nobody asked, HEY! HOW DID THEY DO THAT? How did they bring him back and give him a new set of regenerations? And if they did that...is he STILL The Master we knew from before the cancellation? Well, of course he is. But he has a different body. Is he the Master in the same sense that Ten 2 is The Doctor? If Anthony Ainsley's Master goes through some sort of time loop of evil and meets John Simm's Master...are they essentially the same man in different bodies? How is this switching of bodies different from regeneration?
Let's say you're the Master...and you mean to survive any encounter with the Doctor. Wouldn't it make sense to arrange your own biological metacrisis...using Lucy Saxon in the same way that Donna was used...to create The Master 3?
Imagine all of the youthful vigor of humanity combined with the Time Lord mind. He's faster, smarter and more ruthless than the Master of old. Because look what Donna had to say about how the Doctor's thinking was limited...how he needed that human spark...she was solving all his problems at hyperspeed. Can the Doctor beat this hybrid guy? Or will it take Ten 2 (Let's just call him Eleven) to beat him? Given the choice of living the life he wants, or even living on beyond his natural death after 13 regenerations...Ten would certainly not sacrifice Donna Noble.
But...given a far greater threat to the universe...a Master upgrade, if you will...and a Donna Noble already burning by having her memories triggered...Ten might be willing to Time Lord up Ten 2, give up his Time Lord essence. Ten 2 then becomes the next generation Doctor aka...Matt Smith.
Or...you know...it's just done with that psycho-graft thingee of Cassandra's that allows body swapping. I'm saying we can get Ten 2 to take over the job of universe saving...and send Ten to Rose. But then...that's what I'm always saying, isn't it? :grin:
But, you know, I always return in my mind to that point where Doctor/Donna tells Ten 2 that he should, "Wait for the Doctor." And Ten 2 says, "I am the Doctor." Obviously, the Doctor/Donna does not view herself as The Doctor...but as some sort of bridge being that is predominately still DONNA. Ten 2, however, has no problem at all self-identifying. Makes me wonder if he believes Ten is "The Doctor." And like I've always said...if Ten 2 believed Ten wasn't the Doctor...what would he do about it?