Schlot,
While I like the looks & fit, and I'm not totally dissatisfied with mine, those flaps were a disappointment.
I have two ancestors of the current Filson cap design that folds down. I've never seen them in WWII uniform photos & don't know where they were originally used, issued, or worn.
Both are tagged "L Chessler, June 24, 1941, and Phila Q. M. Depot", along with various stock & spec numbers. They're identical, heavy OD duck on the outside & thick wool lining on the inside. I picked 'em up at a local surplus store about 25 years ago, both unused.
They're still in excellent condition, they're both highly treasured, and I wear one or the other on cold outings in the open cockpit UTV. I can fold the flaps down halfway to completely cover my ears or all the way down to my neck & throat. I've also worn one several times while on long winter walks, and when the wind blows cold & hard those flaps just flat save my ears.
The first time I came across an add for a Kromer made of oiled cotton I thought it'd be great for getting caught out in drizzles, I liked the looks overall, and I just naively assumed the flaps would cover my ears, so I ordered one.
Mine is still a good cap, it's just not the really cold weather one I thought I was getting.
Denis