answer - Viewing the Map.

[srbeers]

No: HPFGUIDX 60516


Fred and George never noticed Peter Pettigrew on the marauder's map,
...edited... Because, otherwise the map would get too cluttered-up.

For example, Harry sees Dumbledore pacing his study and Mrs.Norris,
because he would not want to get caught by either of them while
sneaking out to Hogsmeade.

"Ramyarak"


srb:

I'm in agreement with you on the map being cluttered.

Let us take a look at the map.

But first, let's look at the castle. If you research castles on the
internet, you will see that Hogwarts is a castle of unprecedented
(mammoth, huge, gigantic) size. You might find some castles that have
towers that are 7 commercial stories high, but you will not find
castles that have 7 floor main buildings. Hogarts, in my imaginative
view, has several wings all 7 floors high with very high ceilings, and
it's many towers are much much higher than that. Given that castles
always have very high ceilings, I can picture the main 7 floor wings
of Hogwarts being as high as a 12 to 14 story commercial or
residential building. That would make the high towers in the range of
a 20+ floor high common building. That is ONE BIG MOTHER of a castle.

Now picture that castle's complete floor plans draw in standard
architectural format. That is many many extremely large documents. But
the Marauder's Map is a single piece of parchment. Even if it is 3
feet on a side, the floor plans plus the castle grounds have to be
drawn at microscopic size to fit in that space. 

I've always had the idea that the castle floor plans were layered on
top of each other, and when you wanted to see a specific floor it came
into sharp relief while the remaining overlapping floors fade to a
pale unobtrusive grey. Even if that speculation is correct, the
drawing would still have to be very tiny.

That one factor alone could easily explain why Fred and George never
saw Peter/Wormatail, and why Lupin never saw the second Harry and
Hermione on the map during their time travels. The only thing you see
clearly is the thing you are intensely concentrating on. Everything
else fades to a miniscule blur. Harry constantly refers to everything
on the map as minute (as in tiny, not 60 seconds).

Next, many have speculated that in order to keep the map from being
too cluttered to even use, it is selective in what it shows. For the
moment, let's say it is not selective. Now picture looking at
Gryffindor tower on the map, what are you going to see? A hopelessly
undecipherable jumble of overlapping names. That would certainly make
it difficult to pick Peter Pettigrew out of the crowd. 

Next, Fred and George are at school, the context of the situation
control how they will interpret what the see. In the context of the
school, seeing the name of some underclassmen (Peter P. or P.
Pettigrew) in close proximity to Ron would mean nothing to them. In
that context, where they are conditioned to expect to see the names of
teachers and kids, I seriously doubt that one of them would see the
name and go, 'Hey, isn't that the obscure dead guy that we have some
vague knowledge of?". I don't think so.

Reading the map takes effort and concentration, anything you are not
concentrating on and making an effort to see, fades into the background.

Just at thought

srb

PS: I always thougth a minute owl was a 60-second owl.