[jjblue1]

In Ep 5 Battler says:

Also, at the end of the 1st game, it was revealed that this tale was passed on to people in the future by that message bottle.

......Someone had written about this crime...this tale.

In other words, ......this tale is all part of a world which includes the personal opinions of an observer, namely, the person who wrote that message in a bottle.

In other words, the observer isn't God.
It's a human.

Therefore, there's no guarantee that this description is truly impartial.

By the end of the 1st game, it had already been made clear that we've broken the constant premise of the mystery genre: that the story itself must be seen through the eyes of God.

For that reason, it's possible to doubt even the observer, as well as the witnesses.

He doesn't really talk about someone reading the tale to him... but of someone 'reading the facts in a certain way and writing them down in a tale he... read? witnessed? was read about?'.

And in Ep 6:

"Be an observer for me. An observer of the Fragments Beatrice has woven."

"An observer...? I don't really know what you mean, but no deal."

"In the past, I observed the Fragments through Battler's eyes. ......However, now that he has succeeded the position of Game Master, he is not a suitable observer. I am following this tale with true and earnest intentions. It would be such a waste to observe it through the eyes of Battler as he is now, like reading a detective novel backwards..."

"......Onii-chan is the Game Master?? What on Earth are you talking about?"

"Of course you don't know. You want to know, don't you? ......I too wish to know something. What kind of tale will Battler weave now that he has taken the position of Game Master? ...Furthermore, I wish to search for the truth Battler reached as part of my own mental journey. .........My illness affects me gravely. If I do not think, I cannot even keep my heart beating..."

".........So, ...you want me to read your new picture book aloud to you...?"

"You might as well interpret it that way. In exchange, you will also be able to take part in your own journey of the mind. I do believe that even you have yet to reach the truth. .........I think you want to continue on the journey to find that truth."

So, although Ange is supposed to be a reader, she's called in to observe, to read a 'picture book' for Featherine. The fact she is 'observing' the tale comes up more than once in other parts of EP 6.

When reading text the amount of interpretation we can add is pretty minimal and it will influence mostly the tone with which the quotes from the characters are read and we don't really observe things... we just read them and, at best, we picture them in our mind.

However if what we're supposed to read is... let's say a manga to a person who's not going to watch the scene drawn, we've to describe them using our words. In this way we can influence the plot a lot more.

If the 'reading' Ange is doing is some sort of 'meta' reading, in short it can be in the meta world the tale is being 'seen' by her and she narrates her interpretation of what she sees to Featherine. That's her 'reading' and that's how she can influence the reading. She can't really change the plot of what she's seeing but she's telling Featherine the story using her own words.

And yes, this would mean Umineko basically instead than using 'reader' with the usual meaning of 'person who read a written text' used it with the meaning of 'person who read a situation (and then reports it according to his own interpretation to another)'.

Note that Featherine said she was 'watching the stories' through Battler's eyes and that it was made clear in EP 3 that Battler was called to give his own interpretation of the story (remember the discussion between him and Beato about the magic battle between Beato and Virgilia?), so maybe in a fashion, Beato was being the reader for Battler, as she gave him a fantasy interpretation of facts, and Battler was also a reader, as he gave facts his own interpretation.

... and this is just a newborn theory so it can have holes.

Also...

It was hard to actually like this Hachijo Tohya person.
......However, though this forgery she had written was still in its first stages, ...it definitely felt as though it had something very similar to the tales in those message bottles.
Speaking metaphorically, ......one might call it a scent.
An indescribable stern atmosphere, ......like a stuffy library.
The 'Beatrice' who wrote the message bottles and Hachijo Tohya are different people.
......And yet, this has the same scent as that tale...
......I see.
This is why some of those curious Witch Hunters are so intensely devoted to her...
Their keen sense of smell was able to sniff out that familiar scent......

(...)

Amakusa badgered me to turn the page, ......so I returned to the world of the tale once more.
......Why does her tale have the same scent as Beatrice's, I wonder...
Is it because......she actually has reached the truth, as she claims?
Does this mean that anyone who knows the truth could create an endless number of message bottles?
......Is that what the cat box world is like...?
I see. ......I guess she might also be an Endless Witch.
In fact, ......maybe anyone who knows the truth can become an Endless Witch.
An endless tale, created by the Endless Witches.
The two days starting on October 4, 1986, where my family is being toyed with endlessly.

Ange's explanation about the common scents might be the truth of course... but in a mystery doesn't the Watson's suggestions exist to depiste the reader?
So can this be a hint that Featherine is also one of Yasu's personas?
Or is it just a read herring?