The monkey seat is about keeping flow attached to the underside of the rear wing. Cascade wings are about downfornce and deflecting flow around the front tires. It's conceivable that their Daffy Duct, and all of its constituent parts, does the job of those now-omitted parts. If so, that's great for Mercedes, as it means less drag.
EDIT: Maybe we've been wrong about the Daffy Duct all along. Perhaps opening the DRS flap actually
stops air venting under the front wing rather than activating said venting. Consider the following:
Scarbs says this about Red Bull's blown starter motor hole:
Scarbs wrote:The middle section of diffuser where the SMH lies, is the steepest and thus the most difficult to keep flow attached to. Blowing the SMH acts like an extra slot in a wing, it adds energy to the flow and keeps the flow attached to prevent separation\stalling.
If air collected from the nose scoop is vented on the underside of the front wing
at all times, that vented air would help keep the flow attached by the same principle Scarbs described above. So, it would seem that stopping such venting would then stall the front wing.
That would allow for running a higher AoA that wouldn't ordinarily be possible because of both flow separation and the added drag penalty. The Daffy Duct could eliminate those concerns if it's applied as I've just proposed. (Who needs cascades and their drag then?) Air can also be vented under the rear wing for the same reason - that's still allowed, by the way - and it would eliminate the need for a monkey seat and its resultant drag.
Forgive me if this has already been proposed. I don't give a ton of attention to this thread.