A tin cloth Filson coat takes about 2 years to break in....but about 5-10 years to achieve that perfect balance between new and broken in. I bet you can break in the cover cloth in a few months.
Given (rather huge) allowances for ambient temperature, the tin cloth jacket continues to get a little more comfortable each time I wear it. To my surprise, so does the cover cloth, but it was so (comparatively) limp from the start that the changes are much more subtle. The cover cloth has lost all of the "damp" feeling, it's dry to the touch and warmer to wear, but it still sheds rain very well. The tin cloth, well, maybe 50 percent. Feels dry when warm, but still about half as clammy as it started out when cold. It's only been a few weeks. Both have a remarkably wide comfort range.
So, next question, how do you know when (2-5 years from now) a Filson tin cloth garment is fully broken in? I know it has quite a ways to go, but just wondering what to expect.