Unexpected behaviour when typing ENTER in middle of Rem with children

If I hit ENTER in the middle of a Rem with Children, the part to the right of the cursor becomes the first Child of that Rem. This is unexpected, since this doesn’t happen if I do the same with a Rem that has no Child.

Explanation with images:

Let’s say I have a structure like this:

And I write something at the start of Rem B:

if I hit ENTER, I get this:

I’d expect this to happen instead:

Since this is what would happen if I did that to a Rem with no Children.

Does anyone disagree?