Robbie Coltrane, & Hagrid's future

[ftah3]

I ran across something that Robbie Coltrane said about Hagrid which 
called up a question in my mind about future books.  

I recall reading that JKR, in her capacity as consultant on the film, 
gave certain actors some details about their characters and what 
happens to them in later books.  I know Rickman (Snape) was named, 
and I *think* Coltrane (Hagrid) was as well.  At any rate, even not 
knowing who exactly she tipped off, nor how far in the future (up to 
or past book 4) she drew information for the actors, the fact that 
she did at least tip off some people to future events made me read 
the following statement by Coltrane in a new light:

""He [Hagrid] is a nurturing creature," says Coltrane. "He's got 
Norbert, his baby dragon, and he's not afraid of Fluffy (a huge, 
three-headed dog). 

"But I didn't want to undermine the dark side of him, because he is a 
giant, and giants are unpredictable, as you know." " (from BBC News 
online, URL: 
http://news.bbc.co.uk/hi/english/entertainment/film/newsid_1652000/165
2393.stm)

So far, imho, we've seen very little of Hagrid's 'dark side' 
or 'unpredictable' nature in the books (other than, for example, 
roaring at people for saying mean things about Dumbledore, Harry, et 
al, and popping up with dragon eggs and illegally bred skrewts).  And 
his being a giant, with all the attendent explication of the nature 
of your usual giant (mean! scary! etc.) only just came up in Book 4.

Sooooo...I wonder why Coltrane had the giant side of Hagrid on his 
mind?  In other words, why he felt the need to point out, contrary to 
anything we saw in the film, not to mention in the books so far, that 
Hagrid has an ominously unpredictable nature and 'dark side'?

I wonder what all might have I missed, in the books, that implies 
this 'dark side' of Hagrid.  In retrospect, Ron seemed to understand 
the implications of Hagrid's giant genetics; but still it never hit 
me, until Coltrane's comment, that I maybe I ought to be thinking 
along broader lines than a blustering temper and penchant for 
dangerous pets.

And also, I really *do* hope that Coltrane was speaking from secret 
information about future books ~ because Hagrid is a great character, 
but I think he'd be even more fabulous if he was to undergo such 
fascinating development.  

Opinions?  Enlightenment?  Thoughts, moos, squawks, squeaks or other 
relevant noises?  :)

Mahoney