I'm a little late to the party, but thought I'd chime in on this one. Most of the Madison's have a sandwich of thin foam and chipboard or paperboard/pressboard in them where they wanted them to be stiff. On the Carlyle it's in the flap. If you dunk them and the board gets wet, it will warp (think of what happens to a cereal box when it gets wet). There's no way to get it completely flat again. You can flatten the areas with something heavy while drying to get some of the warping out, but then you risk leaving impressions in the leather, and the "sandwich" sections will take much longer to dry, so you run the risk of mold/mildew.
As for the wrinkles, once the Madison leather is wrinkled like yours is, there's not a lot you can do to fix it. The fibers in the leather have been creased, so it's like a piece of paper that's been folded. You can smooth it out somewhat, but you'll never totally get rid of the crease marks, and the purse will tend to wrinkle there again. I had a Carlyle that I steamed, a while back. It helped get rid of some indentations in the flap, but the wrinkles on the side sections are still there. I just consider them added character - like my wrinkles, lol!
In conclusion, I don't recommend a dunk for most of the Madisons, but that's my opinion only, and you know what they say about opinions.....
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