It sounds like maybe just opening another gate in a room with blinds might actually be faster? Unless they can build boxes fast enough and are okay with it.

It is not that hard to make a box.

Well, alright, she'll take it.

Presently: box.

Fairylights!

There is a very faint pattern near the gate.

Oooh!

"Ooooh!"

"Neat!" Promise notes it down.

If she makes her fairylight grid finer and more numerous does anything more interesting show up?

The pattern is clearer that way.

"...okay now I wanna see if this kind of pattern is the same for all gates or whether it changes, and if it has something to do with size, and maybe with how long it takes to settle—I'm gonna close it and see if it's still there."

"Makes sense," says Promise. "Lemme finish notating this."

"Sure."

She does not watch because watching someone else taking notes is rude.

"Okay, go."

Gate closed!

The pattern changes and it's much, much fainter.

Changes? After Promise notes this she reopens the gate to see if it returns to its old pattern.

It does.

And if she closes it again, back to the same changed pattern?

Yes again.

Any obvious relationship between the two?

"I think I'm gonna try to open a new gate."

Nothing visible naively. "Where? We can map what it looks like now."

She makes a fairylight grid appear where she plans to open it.

Map.

Gate!