On Sun, 28 Jan 2018 09:03:13 -0700, Chris L Peterson
wrote:
It is likely to be worse than either, because it is so bright, and
because it is bright across its entire path, not just in a flare
zone.

No, it's not bright across its entire path. It has 72 reflective
triangular surfaces. Only half of then can be effective of course
since the other half will be in shadow. And less than half of those
will shine towards the Earth, the others will shine into space. So it
will generate some 15 flare zones, each giving flares considerably
fainter than Iridium.

One satellite which really was bright along its entire path was Echo
II which was in orbit from 1964 to 1969. It was a spherical balloon
41 meters in diameter covered with mylar. It did shine at mag -6 or
-7 when brightest, and it did shine continuously during the pass if
it was outside the Earth's shadow. I've never seen any other
satellite shine that brightly, except the peaks of the brightest
Iridium flares, and they are brief.