Yes, I know: "Because then there wouldn't be a story." But why else?

Erm, there's a thing...about crossing their own timeline...and how that's either impossible or very, very bad...or something like that. But mostly, I think it's the "then there would be no story" thing.

And uh, did Rose bring enough mascara on her time traveling adventures? Yeegods.

THANK YOU! It took me longer to like Rose than it would have if her lower lashes didn't make me want to claw my own eyelids off. Gah!

>I like Eccleston; I really do. But I'm not crushing on him,

Humph!

There's several reasons given for why they can't just hop back in time and fix things, first is the one that you cited, specifically that the Doctor's Tardis is very old and frequently unreliable, so hitting any specific point in time is pretty much a crapshoot. The major reason tho, is that once they exit the doors and reenter the timestream they become part of events. As I understand it, the fact that they're somewhere and seeing things a particular way means that those circumstances HAVE to be that way when they see them, otherwise there's a paradox. For instance if the Doctor steps out of the Tardis and sees a mustard jar on the table, he cannot hop back in the TARDIS, go back ten minutes and remove the mustard jar, because it needs to have been there for him to see it otherwise causality breaks down. This didn't used to be as much of a problem back in the day when you had the other Time Lords futzing around making sure that time stayed on an even keel, but now with the Doctor the only remaining Time Lord, there's no one left to clean up the mess and those thingees show up.

But, until and unless he enters a future point in time where he KNOWS someone died at a particular moment, then he's generally free to act. I figure all the time changing the bad guys did/do/will do is because since they didn't know how things were supposed to be at the point in time at which they entered, they weren't affected by Paradox. Then again, this explanation is half-fan-wank and half some of the stuff previously stated on the show.

As for the nanogenes, well they were pretty much a one shot deus ex machina, but my guess for why they didn't keep 'em around was probably that they had too great a tendency for abuse if left in untrained hands, so he had to get rid of 'em.

Okay, I'll ask the really stupid question now and get it over with: With a time machine on their hands, why don't our heroes jump into the Tardis anytime something goes horribly wrong, go backward in time a bit, and fix the circumstances? Yes, I know: "Because then there wouldn't be a story." But why else? Something to do with it being difficult to end up on exactly the right day every time?

Wihtout saying too much you'll get to an episode soon about interfering with the time, that might answer some of your questions.

I thought she should already have seen "Father's Day" before meeting Jack?

Hi there. :) Yeah, if you mean the "Father's Day" episode, I've seen the bad things that emerge if you mess around with certain events--but actually I think that was more because the Doctor and Rose were there in duplicate and therefore caused a paradox, which was the major no-no. *shrug*

Ah, Nine/Rose/Jack - my ultimate OT3.

Isn't Jack just the most wonderful big, slutty, pansexual hero ever, though?

Ten is totally darling. Totally. I have the biggest crush on David Tennant, but I think you knew that by now. ;-) I can't wait for you to officially meet him!

Aww! I think you'll love him, too. ;-)

I must admit I'm enamoured with Nine. I mean he's not conventionally handsome, but when Eccleston smiled it was all over for me. He has the best smile. I'm still getting over losing him at the end of his first season there, though I do like Tennant, too, just not quite as well. It was fun to see Eccleston showing up on "Heroes" last year, though, playing another great character. Hope invisible Claude comes back this season!

From the canon standpoint, the Doctor cannot really control the TARDIS nor does he fully understand it (he is learning as he goes along... he stole the TARDIS btw)

There is an early episode of from the Classic Who series which explains the concept of Time Meddling (the episode is called "The Time Meddler"). The whole future of every year and time on Earth (or any other planet/dimension) will change if one aspect of time is meddled with. Later on in the series, this concept is expanded on as the "Blinovitch Limitation Effect" -- a time traveler cannot "redo" an act that they have previously committed (I think this is connected to the First Law of Time), but if you attempt to do this a dangerous energy discharge will result if two temporal versions of the same person.

/being a geek

A new fandom! With canon stretching back more than 40 years, I'm afraid there's no hope of consistency -- but any inconsistencies can be explained away as the result of not-quite-paralel timelines. Although the revived Doctor has production values (a shameless attempt to appeal to Americans), I miss the old shows, when it was obvious that the special-effects budget had run to 50 or even 75p!

Don't worry, I was just kidding...

Ewoks appeal to female viewers? I can see I still have a lot to learn...

And Lucas shamelessly (well, I don't actually know whether he felt shame, but the man who gave us Jar-Jar must have a pretty high shame threshold) copied the Ewoks from the Fuzzies late H. Beam Piper's "Little Fuzzy" children's novels -- I wonder if he paid any royalties, or if Piper's estate sued?

And I never saw the new Doctor until after I'd seen Goblet of Fire, so I keep thinking "Don't trust him! He's a Death Eater!"