This is BY NO MEANS a comprehensive test, this is just me messing around, sharing my not-so-scienfitic results with you.
This pictures shows the fabric and the tools I used.
I used Kona White and Kona Charcoal as the fabrics (because they were close), and the tools were: blue Mark-B-Gone pen, white Crayola colored pencil, white Dressmaker's Marking Pencil, yellow Crayola colored pencil, black Frixion pen.
In this picture, I simply spritzed the fabric with water to show what disappears. Or smears... :)
Here I scrubbed the fabric to simulate washing. Obviously it would be a bit better with washing, but I didn't want to take the time to do that. :)
You can see the white marks disappeared from the Charcoal fabric, and the yellow and black Frixion marks smeared and did nothing.
Here's a close-up after scrubbing to show that the yellow was almost gone, and that you can't see any other marks - colored pencil or Frixion pen. Remember that...
Oh, I ironed it! Lookie lookie!
And here it is after being in the freezer (or a cold car in the winter) for 5 minutes:
Hmmm....not the best results....
And then I ironed it a second time:
So, I didn't take process pictures, but I decided to see what would happen if I scrubbed and rubbed it with soap, trying, mostly, to get the yellow colored pencil out. I then ironed it (to dry it, really), and froze it again. Here it is after 10 minutes in the freezer:
I think all the marks are much less noticable after this, but everyone is entitled to their own opinion.
I will say this. Last February, I made a quilt for Kelly's baby, Tucker, and used the Frixion pen to mark all my quilting lines -- then hardly sewed directly on them at all! And I used it to figure out what I was going to write on the label, then changed it. I thought the Frixion pen would disappear forever at that point, but learned later that it doesn't. I asked Kelly yesterday, and she said she hasn't seen ANY marks on Tucker's quilt, and she's washed it multiple times. She lives in Florida, though, so the quilt probably hasn't seen freezing temperatures... :)
So, that's it!!
PLEASE feel free to share what kind of marking tools you like to use, and why. I know all 12 of my readers will be happy to find a good one! :)