In stock KSP, all parts using the drag cube drag calculation model (basically any part that isn't physicsless or a wing) will generate unrealistically more drag when not perfectly aligned with the airstream.
This mod alters the way in which the influence of different drag cube faces gets added together, causing the generated drag to be much more stable over different orientations. It does not affect the drag generated by any parts if they were already aligned with the airstream, so it won't improve the theoretically optimal performance of crafts. You will however have significantly less drag when pitching slightly up/down to steer your craft, so it is significantly easier to get close to optimal performance.
Some examples of how the behaviour changes:
In stock KSP, the drag of a spherical dumpling tank can increase up to 70% depending on orientation. With this mod, it is nearly constant.
In stock KSP, the drag generated by a long part at 30 degrees from the airstream, is about ~50% of what it would be at 90 degrees. With this mod, it's 25%.
In stock KSP, the drag generated by a long part at 2 degrees is double of what it is at 0 degrees. With this mod, this only occurs at 11 degrees.
Dependencies:
Raw stats are from the beginning of time until now. Each follower and download entry represents one hour of data. Uneventful hours are omitted.