Why on earth....

[Brooks R]

No: HPFGUIDX 709

....are some of the various protections along the route to the 
Sorceror's/Philosopher's Stone, puzzles at all?

The Sphynx riddle in the maze in GoF fits in.  The competition SHOULD 
be a puzzle.  But in SS/PS, they are trying to protect something of 
great value and dangerous power.  So why use solvable puzzles?

Is this some inconvenient wizardly honor code?  To a SMALL extent it 
can be explained as a precaution, so someone else can retrieve the 
Stone in case something happens to Dumbledore.  That way some other 
smart good guy can get through them if needed.  It gave lots of 
nice quest/adventure/tension for the climax of the plot for Our 
Heroes.  

But why have puzzles that *bad guys can solve too*?

Think about it!

Fluffy is a reasonable guard - he can be diverted, the only puzzle if 
finding out how.

The snareweed also falls into the category of a perfectly reasonable 
trap.

The Troll too is a dumb guard, and the heroes, conveniently, do not 
have to face him anyway.

The Flying Keys are more of a stretch, but somewhat reasonable.  
Someone could be expected to try all of a large selection of keys 
until they find the right one, if they are just sitting there.  
Eventually even a clumsy wizard might be able to catch the right key.
 
OTOH, what if you made several keys  of different heads still fit,
but 
some of them lock the door more tightly, so that even if you find the
right key you may not know it because you need now to use it more than
once?  

But the chess game?  Why bother?  Why not just transfigure a set of 
statues or something into guards, with some kind of password 
programmed into them?

Similarly, why bother with the logic puzzle of the potions?
Just put a bunch of bottles in there and let someone take their 
chances!  The person who sets it up knows the correct ones; other
than that what does it matter?

On the other hand, Dumbledore is right about the Mirror of Erised. 
It does work nicely as a protection.  Although it is really not clear 
what kind of spell is used to get the stone hidden in it that way.  
Alternately, this may be a not-specific alternate power of the mirror 
itself - perhaps there is a spell to conceal something by placing it 
into a mirror's image, which after all might be a parallel universe.

So of all the protections, two of them seem quite inadequate against
a smart bad guy, and the Flying Key could almost certainly be caught 
eventually.  It seems like the puzzles are counterproductive as 
protections.

Brooks