Slughorn - hiding more than meets the eye?

[vmonte]

No: HPFGUIDX 136528

hg:
If Dumbledore was a new teacher when he went to the orphanage, it
would be 1938 that he and Slughorn started teaching at Hogwarts
together. 24 sounds a good age to get a teaching job, perhaps? His
birthyear would be 1914, he'd be 57 in 1971, and goodness knows what
was happening then. (Voldemort was getting powerful?) That would put
his current age, by the way, at 82. Do the math in the reverse,
speculating the locket was found in 1980 and he was 57, then he'd be
73 now, and the other lucky day would have been 1947. Not possible
because he'd then have been 15 in 1938. One more little speculation:
what if he aided Dumbledore in his defeat of Grindelwald? He'd have
been 24 in 1945 and born in 1921; second day would be 1978 (?) and
he'd be 75 now.

vmonte:
Grindelwald was defeated in 1945 by DD. Did DD then show up immediately
afterwards at Hogwarts or was he already there and just took a side 
trip to defeat Grindelwald? What is the connection between Grindelwald 
and Voldemort? 

There are a few odd things about Slughorn's class that have been on my 
mind. 

1. Why are we all of a sudden seeing the Draught of the Living Death
potion? (The potion that Snape mentions in year one?) Why wasn't it 
used? I know this is a weird question but Harry always ends up using 
the spells, potions, and animals or creatures that are introduced in 
each book. Will it be used?  

2. What is Slughorn going to do with all that spider venom?

3. Did you notice that Harry is learning more from Snape now that he 
is no longer the Potions Teacher? 

4. Was there also a vat of polyjuice somewhere? I cannot remember if 
Draco brewed this himself, or whether it was in Slughorn's class? Was 
this really only used to turn Goyle, and the other thug, into girls? 
(Why show boys turning into girls? Will a girl, in book 7, turn into a 
boy? Let's just say that I'm going to become very suspicious if Harry 
gives Ginny a lock of his hair before the big Voldemort showdown.) 

There seems to have been really useful items that could've been used 
to save DD that were seemingly never used, why?

5. Why was Slughorn introduced into the story? Why does he never 
mention what Snape was like as a student? (I suppose Harry will look 
into Snape's past in the next book.) Was Slughorn introduced by JKR to 
show that not all Slytherin's are bad? (Sure, he still has Slytherin 
traits, but that does not necessarily mean that he is a DE.) 

6. I like how Hermione mentions that all the time-turners were 
destroyed in the DoM. Were they? 

I'm sure there are more things to add. Sorry if I've repeated anything 
anyone might have mentioned.