Today I present my most sackiest sack suit. It was a relaxed fit 25 lbs. ago, and now, well... Anyway, I still like wearing it.
SB - I really like the shape of those trousers, very classic. I see that you are a fan of the besom pocket (a rarity on this board), any particular reason why? Feel free to ignore if this has been discussed prior to my thread participation.
There's no drape, exactly the opposite, which is kind of the definition of the sack coat. Check this out to read a good bit about drape and the sack cut.
How was that an uniformed mistake? All suits "drape." Some suits have a "draped chest" -- which is often shortened to "drape."
That suit does not have a particularly clean chest. It doesn't have the waist suppression of some drape cuts.