Defending Celestia part-2

Continuing with the accusations and response, we have Celestia's handling of the Nightmare Moon situation.

ACCUSATION: That Celestia hid the elements in a weakly defended manner the likes of which were just waiting for NMM to come and whisk them away; waited until the last second for Twilight to act; depended on a weak chain of events in order to secure victory; didn't give the mane-six any guards for protection before, during, or after the events of NMM; took the elements back to Canterlot away from their bearers; didn't have the elements looked at, researched, experimented upon or otherwise attempt to further weaponize, reproduce, or present adequate defenses against the EOH in the case of them being used by an opposing force.

RESPONSE(S): Let's get the easiest parts out of the way first.

-The guards are useless! There is only one time I can recall AT ALL wherein the guards were ever able to actually stop somepony, and that pony was Fluttershy during "A bird in the Hoof". Furthermore, they were so out of the loop that a single unicorn (Twilight) was able to convince them that Fluttershy was indeed "on the list". With security that tight, I wouldn't even need a fake ID to bluff my way in.

-Celestia informed (allowed Twilight to learn) about the NMM situation on day-1, it wasn't until day-2 that Twilight went to Ponyville, it was the following morning (or it would have been morning) and ergo day-3 that NMM attacked. What's more, It appears that Celestia knew that Twilight would need her friends, and that they would need to BE her friends in order for the situation to work. That would rely on Twilight not being able to see them on her terms, and be taken in by them on their terms instead. Was it "the last minute" yes, was that to her discredit? No, not really.

-the EOH were not poorly defended. Consider this, they're a McGuffin, a rare entity, a set that, if separated, are worthless! The last thing you'd want would be to have some wandering pony just up and snatch them because they looked cool or whatever. So the best place to put them would be where no wandering pony would, well, wander. Secondly, if they were just left there, as NMM that would be one place I would search, definately, but upon seeing them in the open in the old castle like that, I'd get suspicious, I'd smell a trap, I wouldn't touch them, just ensure nopony else did either. Third, If the elements were left in Canterlot, Twilight and the gang would have had a more difficult time retrieving them because that's likely the first place NMM would go to look for them and it's more isolated than the EFF, just think about all those railroad bridges that could be easily destroyed. If they were hidden in Ponyville there was the chance that somepony else would find them, there was the chance that NMM would find them, and there was the chance that Twilight and the gang would NOT find them. All that put together means that the single safest place for them would be... right where they were in the show.

-Now, speaking of the elements, the elements are the single most powerful weapon that they have to use, (at that time) period! As such, it is imperative that they not be broken or otherwise messed with, potentially breaking or complicating their use and/or function. As such, the only kind of examination that could be afforded would be a simple and non-invasive one. Anything deeper and you risk a heck of a lot of (most likely) bad consequences.

-Finally on to the last bit.

There are two key events that dramatically affected how the plan turned out.
1, Twilight announced herself as knowing who NMM was when all other ponies did not.
2, NMM saw Twilight and the others in the library talking about the EOH

That's it, those two events. Consider that, if Twilight hadn't announced herself, she wouldn't have been singled out by NMM as being worth following, and without following Twilight, NMM wouldn't have been able to spy on her and learn where the elements were in the first place. And without knowing where the EOH were, NMM would have probably spent hours, maybe days (not that "days" has much meaning under eternal-night conditions, but that's nitpicking) searching both Canterlot and Ponyville, searching in vain. It is also worth noting that the only obstacles the mane-six actually faced were all because of NMM's interference, it's as though something, or somepony, had gone in and made sure none of the inhabitants and monsters were anywhere near the path from Ponyville to the castle. The closest thing to an obstacle that they faced was the Manticore, and that was only an obstacle because of what NMM did to it beforehand.

It is also worth noting that NMM only showed any sense of power in 2 occasions, the first being when she showed us how useless the guards were (not requiring much power IMO) and when facing down Twilight directly and alone. In fact, that latter one was more a sense of bravado than it was any actual power. It's almost as though she didn't have much power and was trying to conserve it, play it safe, use cheap tricks instead of just flat-out attacking.

I'm gonna throw out some headcanon, but it's a pretty good one I think. I say that NMM was victorious over Celestia... but only barely, and that the fight cost her and she needed time to recover. But she also couldn't afford to let any other pony know that, so she decides to play the crowd, show a little power to throw the guards around, then go whisking herself away to both go spying, searching, sneaking and most of all, recovering.

Now, I believe I've covered all of the accusations thrown so far so it's time for...

CONCLUSION: Celestia's actions were reasonable as per the situation, which was threatened by two events, but not enough to stop the plan from succeeding.