That is not the impression I have received at all.

But it might be nice if it was true...so maybe I'll pretend it is.

It actually sort of follows if you read through the examples.

If you want a weapon that also protects you from damage through the mechanic of armour, why not use a shield? There's a reason that a lot of pre-modern armies used the things: They're good protection and a quite passable weapon at the same time.

It's really weird. The game is normally so abstract, but it has specific rules for falling.

And they are terrible.

Maybe that's why the book seems so apologetic about providing them.

They feel to me sort of like they were glued on.

Me, I'd just use Consequential rolls. Throw together some sort of guesstimated correlation between distance and damage, roll, and move on. It seems a lot more applicable than saying, "Well, you're falling 50 feet, so you're taking 25 Stress. I, uh, hope you have insurance."

I mean, I know that in the real world, an uncontrolled fall of 50 feet just normally kills a dude. But so does getting hit by a big truck going 60 MPH. Why one is 25 Stress and the other is weapon:5, I don't know beyond guessing that the damage rules were an afterthought.

(Also, my spell checker recognizes, "Guesstimate.")

What if the strength of the circle is based on street traffic around the road outside, and construction blocks that road off for a while?

There's something from the Exalted setting that has a really close relation with this idea: The Order Confirming Trade Pattern.

Without getting too much into the background (and thus way off topic), it's a pattern of trade networks designed to keep back the chaos that eats at the edge of the Creation. That chaos is filled with monsters and all sorts of nasties that want to rip the world apart, you see.

The many, many people that walk the roads of the Order Confirming Trade Pattern each grant a tiny amount of themselves to it. Although this doesn't take anything remotely measurable from the individuals, multiplied by all the people that travel the roadways it builds tons of power. All that power is concentrated into using the Pattern to hold back the tides of chaos.

This could be something really similar.

So each person traveling on one of the circle roads gives up a tiny bit of their life force. When I say tiny, I mean they need like 5 seconds of extra sleep to make it up, or something equally harmless. But with all the people that drive one of the roads every day, it builds a rather large charge.

The way that the area is constructed, each of the outer concentric rings channels the power it collects through one of the spokes and into the inner ring. Since there are several spokes, it doesn't really matter if one is blocked, because the excess power will just flow down another spoke.

But what indeed happens if the whole area is shut down? It's true that a magical battery that big could have built up a really epic charge. However, it's not infinite. It can be used up. And when it's gone, that's when it can be broken into/ out of.

That's actually a really interesting idea to run as sort of background noise. Come up with some innocuous Theme related to traffic and the roads, then mention during several stories the increasing amounts of construction. Play it up as flavour, and occasionally make it interfere with getting somewhere on time.

Then spring a major story involving whatever it is being kept in/out of the church. As soon as they understand the nature of the protection circle, the players will suddenly realize that you've been building up toward this for several stories.

Consider this, Harry has a fireplace which he uses to heat his apartment.  If there were a series of circulation pipes running between a water tank and the back of his fireplace, Harry could both heat his apartment, and have a source of hot water.  Taking things further, by having a large tank of heated water in his apartment, it would actually help regulate the temperature of his apartment, since water is slow to both heat and cool.  In order for his to be able to actually use this though, there would need to be a certain amount of re-plumbing the pipes...

Redoing the pipes in your apartment and ripping apart the chimney at the same time is going to be really expensive. If you do it yourself, you're going to need to know what you're doing, and then it's going to take a while (especially if people keep attacking you while you're doing it). Either way, it's really resource intensive.

It's way easier to just take a bath. Fill the tub part way with cold water. Heat a pot of water over the fire and add it to the tub. Repeat until it's full.

Those times you're really gross, you can either rinse off in the cold shower, or you can wipe off the worst of the grime with a wash cloth and then dump some water over your head. Then rinse out the tub and proceed as above.

Yeah, it's a bit of a stop gap. On the other hand, you don't need to redo the plumping in your whole apartment and rip apart your chimney while you're doing it.

If you're dead set on taking a hot shower, you can always rig something up. Put a hook into the ceiling that can easily hold 50 pounds. Fill a 5 gallon bucket with a combination of tap water and hot water. Put it on the hook (which can hold it, because it's only 40 pounds). Attach a hose to it somehow (and there are lots of ways to do that). Let it rip.

I mean, a 5 gallon shower isn't going to be record-settingly long, but it's better than an ice cold one. And you can rig up this sort of system in 20 minutes. Better yet, the highest tech thing involved is a spigot, and the rest runs on gravity.

You're reading it wrong.  Or perhaps they typed it wrong.  Try it this way:

"Each target that fails to defend, with Might, suffers a 2-shift hit plus any increase from the attack's margin of success."

I am not reading it incorrectly. You're quoting it incorrectly. The way I quoted it is the way it is in the book. The sentence as written in the book is a single clause, and it has a single piece of punctuation: A period at the end.

Adding those commas that aren't in the book doesn't swing it away from saying that you need to defend with Might. Nor would parentheses or dashes. So not only are you adding something that's not in the book, but the things you added don't do anything to make it say something other than what it said before. You've only changed the timing and a little about the emphasis.

Wind designed to push a player back could be defended by Might.  A spell that suffocates should be defended by endurence.

The problem isn't that the rote says it can be defended against with Might. It says it must be defended against with Might.

Saying that you can defend with Might (or Endurance, or whatever) adds more ways to defend against something. You can still dodge the earth opening and trying to eat you if you want to. But if the player decides that Might sounds better for whatever reason, they can opt for Might.

This is in stark contrast to saying that you must defend with Might. Now Might is your only option listed in the book.

Also, how would a Zone-Wide attack be defended against, narratively? I mean, if for example Harry did a Zone-Wide Fuego, how could someone justify avoiding being hit by it, other than someone who would be able to dive out of the zone?

Mechanically, you use a skill with a trapping that allows you to defend. You need no more justification than that, because that's how the game works. (I mention the mechanics because your second question here mentions mechanics.)

Narratively, there are many examples of possible ways to defend against such things. Cover and dropping prone were mentioned above.

Just because an attack will hit everyone in a zone doesn't mean that it fills the whole zone. All you need to do to defend is be somewhere the attack doesn't reach. You can move between streamers of flame, duck behind something, duck under the attack, jump over it, or even slice it in two with your bad-ass magical sword.