Retouched or not?

There is something strange about the drawings in the Rough Art Book that came with manga book 14. Arakawa is either a genius, or the drawings have been retouched. Why? First...

... this is an excerpt from my last 4-panel. This process is exactly the way it was drawn. No retouching. (Layers are so convenient...)

Now, the drawings in the art book. Most of them are in this stage. They look very finished and not rough at all! Where are the sketch lines for the underlying structure and proportion? There's not even the basic cross in the middle of the face to determine the mid line and angle. But I'm more puzzled to see the lack of a string for the beaded necklace!

On a closer look, there are some traces elsewhere. Like the cross around the collar bone of this Hawkeye, and the head and thigh of this sitting Ed. Roughed-in structure lines should be rougher and usually contain mistakes, like these two. But they still look way too refined.

Traces are also found on this Scar. Normally, wouldn't you need more structure lines for dynamic poses like this? I usually start with a stick figure to determine the angle of the spine and limbs. Then joints are "circled" in, and then mass is added. In other words, I need at least this much (far right) structure lines to draw poses.

Actually, Arakawa seems to used circles too. You can see them in this one. There are also very slight traces of a stick figure, mainly on Ed's legs. This is where I find most suspicious. Poses like these are way too difficult to draw without any stick figure. At lease for me. Take a closer look at the drawing on top. Not only is this pose dynamic, it's in perspective too! Yikes!!!

And this hand-stand Ed has a lot of unsure lines, but seem to have been erased! OK, on this one, and this one only, looks like the erasing happened before publishing. But the rest... with today's technology, it's not that difficult to completely eliminate the sketch lines.

Last but not least, the drawing Arakawa did especially for this art book. I'm 120% sure that this is inked with pencil using a light table. Structure lines are almost non-existence! The only obvious one is on Al's face. That's it! With this many overlapping characters, I simply cannot believe she did it without a more primary sketch first.

As to whether or not the drawings were retouched, I cannot come to a solid conclusion, but I do think the possibility is very high. Perhaps to improve image quality, perhaps to keep Arakawa's drawing method a secret....