It is somewhat implied that Dumbledore "appeared" on Private drive in the first chapter, but that could be put down to many magical things.

 

I like the theory that Harry simply misunderstood Hagrid. He didn't say he 'flew' but that he 'flooed'. Since Harry didn't know about the Floo then, he simply must have assumed that Hagrid said something else.

Not exactly supported by canon text, but it makes sense to me.

 

I thought Hagrid used Sirius' enchanted bike?

 

I'm talking about the hut in the sea, not when Voldemort was defeated.

 

Hmm, that is odd indeed. I doubt there's a broom that could seat Hagrid, no matter the charms.

Maybe he uses his umbrella, like Marry Poppins, and just floats up into the sky?

 

Or maybe he flew on Thestral and when he arrived, he sent that Thestral back. It's doubtful that someone could see it, when it would fly above clouds and it would be invisible to most perople neverthless. Statute of secrecy would not be breached in this way and Hagrid would not have to cast any spells.

EDIT: According to W.O.M.B.A.T. test question number eleven, transportation by Thestral could be breach of the International Statue of Secrecy. Oh well.

 

Again, it calls into question whether a Thestral could support someone of Hagrid's size. He's not exactly a fifth-year student at Hogwarts on his way to the Ministry.

 

They certainly pull carriages full of students easily enough.

I always liked that Thestrals were sort of the Hogwarts counterpart to the Abraxan that brought the Beauxbatons student delegation in GoF.

If Hogwarts had to show up at another school for the tournament, would they just have a massive carriage pulled by semi-invisible Death Steeds?

 

I'm not sure if they would do that, but it would certainly be the most awesome ride ever.

 

Anyone who could actually see what was pulling it would know not to fuck with Hogwarts.

Anyone who couldn't would chalk it up to more of Dumbledore's madness.

Sort of a nice parallel to Albus himself. Anyone who's seen him fight (with the Elder Wand [that has a Thestral Hair core] no less) knows not to disrespect. Anyone who hasn't looks at him strangely, wondering why he's there until he manifests a fully-sized and exquisite armchair out of the fucking ether without breaking a sweat.

 

Which is in itself a sign not to fuck with Hogwarts. You don't want an insane, old, powerful wizard on your head.

 

What's the problem with Hagrid flying over with a broom (then shrinking it to put in a pocket) but not feeling confident enough to keep an 11 year old from falling off?

 

It could be a huge problem involving shrinking and the charms on the broom interacting badly. However, in the interests of avoiding another 5 page derailment, I will say 'no problem at all'.
This does bring us to another plot hole. Hagrid gives a pig's tail to Dudley. That is the sort of thing they sort out at St Mungo's, not in a hospital 'to have the tail cut off before he goes to Smeltings'.

 

I don't see how that's a plot hole. The Dursleys would never opt to go to wizards for help if there's even the smallest possibility that it can be solved by 'normal' methods.

I suppose perhaps you could argue that the magical reversal squad should swoop in to fix it, afterall any normal situation where a muggle has been afflicted in some way by magic has to be dealt with somehow without the muggle turning up at St Mungos by chance. Unfortunately for the Dursleys, though, Hagrid was given permission to use magic. Thus his magic use wasn't flagged up as 'something possibly needing immediate reversal' and the Dursleys would have had to draw attention to it themselves. Something they'd never do. If they even knew how to.

 

Wouldn't an operation to cut off a tail from a human be the sort of thing that smmons obli -- wait. maybe it did, and the obliviators wrote it off as accidental magic from Harry?

 

Or the obliviators came and removed the tail, and gave the Dursleys a memory of having it removed at a Muggle clinic.

 

If I remember my canon correctly, the Dursleys drove Harry to King's Cross because they were going to London to chop off the tail anyway. Seems like a minor point, but it could mess with your theory.

 

They could have been given directions to a clinic, and find out that the clinic is actually St Mungos, and that they had to have it magically removed, and then their memories were modified to fit what they had expected.

 

JKR said the Dursleys took him to a private hospital to have it removed, saying it was a wart grown out of control. http://www.accio-quote.org/themes/dursleys.htm