Well, after installing some additional Barrina LED's in the shop today, I had some extra time and decided to further investigate this issue. It just seemed baffling to me that Festool would so totally miss this fine point when the arm & edging plate are designed specifically to be used with both the 1010 & 1400 to produce smooth edges while trimming.
I also noted that at least 3 each 1010 owners verified this out of square condition and 2 each 1400 owners also verified this condition to be true, while only a single owner of a 1400 said this was not an issue. That also raised flags anecdotally because if the proper orientation is actually 90º, then there should be more people saying their set-ups were at 90º. The information being received was trending in the wrong direction.
So, I just sat down with the 1010 in-hand and thought through the process including how the router is used & oriented for trimming operations. After much twisting, turning and squinting I realized that the edging arm & angle plate are not supposed to come to a 90º angle, but like the MFK 700, the router bit needs to be angled slightly to prevent damage to the surface being trimmed.
I measured the offset of the router bit and sure enough it came out to approximately 1º.
I then decided to verify this condition and take a photo of it so that we can finally put this topic to bed. I mounted a 1/4" drill backwards into the collet of the 1010 because that would give me a straight & uniform sight-line to pick up with back lighting. It's a lot easier to see the offset as opposed to measuring the offset.
In the photo, at the very front edge (LH) of the panel and router interface there is a line-to-line contact and you can see that as the distance increases the space also increases. The router base is on the LH side while the edging plate is on the RH side.
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